97 Cadillac Seville Multiple error codes and symptoms CRAP!!

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#1
Hello
I have a 97 Cadillac Seville that I am trying to get going again. The on board error codes P0300,0308,0108,0603,1599. My code reader picks up P0301. She has to be hit with starting fluid to start cold, hard to start after being warmed up for a few
minutes, and won't start until it cools down after it has been driven until it is completely warmed up. If I push down the accelerator past 1/2 quickly the engine almost dies(acts as though starved for fuel) and while idling it will slowly flood until it dies on restart the engine speeds up like it was overloaded with fuel for just a minute or two and then the cycle starts over with the smell of unburned fuel coming
out of the exhaust. It will loose power while driving,
backfire loudly, and then drive ok for another hour or two.Since purchasing the car it has lost a huge part of it fuel milage 15 to 20%.
Any direction or advice would be greatly
appreciated

Thanks Rich
 

billr

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#2
I would focus on the MAP sensor first, that could account for a lot of the other codes. It is fairly easy to test, although an intermittent might be hard to catch. Also, it is used in a lot of other GM products, so isn't hard to find or expensive.
 
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#3
try not to post in multiply forums, it makes following suggestions and repairs hard to follow. repeat ideas and suggestions. If cherry picking diagnostics, its hard to describe a diagnostic plan, not knowing all you have done under advice elsewhere.

do the basics- FUEL PRESSURE and leak down rate, spark at several cylinders- how do plugs look?
Vacuum leaks AND inspect the MAP sensor (P0108) ... what tools do you have - scanner, fuel pressure gauge, vac gauge, DVOM?

Are you disconnecting the battery - somehow trying to erase codes?
tell us vehicle history- repairs, maintenance and all modifications or added components
 

billr

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#4
How long was it sitting, was it outdoors? Was it running fine before it was let sit?
 
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#5
Hi
The car sat for about 6 month in my driveway.
It was running, but poorly with the same symptoms that I called out in my post, with the exception that the last time it was driven it was taken about 10 miles from home and would not re-start even using starter fluid. So we are a little bit better off now, just because she decided to start.
Of course it would start in my driveway.
Thanks for your response
Rich
 
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#6
Information Kev2 requested;

I bought the car a little less than 2 years ago.

The battery has been dead for about 6 months.

The tools I have scanner,vac gauge, and any other specialty tools I should be able to borrow or rent from O'Reilly's.

Vehicle history- repairs- I replaced the water pump, fuel filter, and spark plugs

maintenance---Oil changed every 3,000 miles

There have been no modifications


I haven't made any changes under other peoples advice, I have tested the plug wires using a multimeter. checked the spark plugs they seem okay.
 

billr

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#7
I think you are going to need a scan-tool or PC link that can display live-data in order to resurrect this beast in a reasonable and cost-effective manner. There are too many sensors and engine parameters to guess about when you get into something in this condition. In the meanwhile, start by taking compression and fuel pressure, and test that MAP sensor. Tell us if you need help with those procedures.
 
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#8
agree - do the basics,
P0108 the MAP issue- definitely would skew the fuel metering, knowing what the voltage is would guide us and the scanner is the go to tool - in freeze frame OR live data what is voltage from map?
A thought - remove sight shield inspect map wiring for- pinched, twisted, rubbed thru, OR secondary ign wire to close to harness.
 
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#9
Wow you drive a Cadillac, I am asked, most people can't tell one year from another, are you rich? No, its because these cars are so complicated, cheapest car to purchase. But get a shop manual and go through the entire electric system so it can be reliable.

Test drove a 2012 CTS, for 40 grand more than a Cruze, only gained one more inch of rear seat floor room that use to be an advantage of buying a Caddy besides all those goodies. Not interested anymore. Hood is nine inches longer to cram a huge V-8 in there for HP you can't even legally use.

Worse problems were in the MVAC automatic climate control system, problems are normally simple, but extremely difficult to get to. And not one or two, but hundreds of them. Ha, getting too old for that, never thought I would switch to a Chevy, but a lot less grief. And still gets me there.

Get a shop manual.
 
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#10
Okay guys
drove car yesterday, after replacing the fuel pressure reg.. the pressure went from 20 lbs to over 30lbs still about 1/2 what it should be. Need too replace fuel pump? It is running a little better, but not close to right. Overheating after about 40 minutes in town coolant level is okay. threw several new codes, map sensor, misfire on cyl. 1, bank one lean. most seem to tie back to either low pressure or consequences of running with low fuel pressure. Does this line of thought make sense to anyone else
 
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#11
Stored Codes
P0107MAP Sensor Circuit Low Input


One Output State Monitor strategy tests outputs for opens or shorts by observing the control voltage level of the related device. During testing, the control voltage of the device should be "low" when it is commanded "on", and it should be "high" when it is commanded "off".Some of the output devices monitored by the CCM are shown below: * A/T Electronic Pressure Control (EPC) Solenoid * A/T Shift Solenoids (SS1, SS1, SS2, SS3) * A/T Torque Converter Clutch (TCC) Solenoid * Cooling Fan Relay * EGR Control Solenoid * EVAP Control Solenoid * Fuel Injectors * Fuel Pump RelayA second Output State Monitor strategy tests a device for its "functionality". In this case, if the PCM sends a command to a particular output device, it can monitor specific input signals related to that device for expected changes in order to verify that the desired command was actually carried out. For example, if the PCM commands the Idle Air Control (IAC) motor to a specific idle speed position under certain operating conditions, it expects to see a specified target idle speed happen. If it does not detect the correct change, the CCM fails that particular test, and a trouble code is set.
Output State Monitor Graphic


Freeze Frame Data

The PCM stores the current engine operating conditions at the time a trouble code is set in a special portion of memory called Freeze Frame. This important information can help pinpoint the cause of the trouble code. It can be retrieved with an OBD II compatible Scan Tool to help diagnose the problem.
Repair Verification Process:

An example of how to drive a vehicle to verify the repair of a trouble code related to the CCM on these vehicle applications is shown in the Graphic below.
Repair Verification Graphic


Copyright 2010 IEC. All Rights Reserved.
Portions 2012 Cengage Learning. All rights reserved. Used under license.
P0135HO2S-11 (Bank 1 Sensor 1) Heater Circuit Malfunction
Conditions For Setting This Code:

DTC P0101, P0102, P0103, P0117, P0118, and P0134 not set, ECT sensor signal has dropped at least 50F since the last ignition cycle, engine started, system voltage over 11.0v, average HO2S bias voltage from 352-546 mv, engine did not stall in the test, and the PCM detected the HO2S signal remained within 150 mv of the bias voltage (450 mv) for too long (depends on ECT and MAF at startup).
Possible Causes:

HO2S heater ground circuit is open or has high resistance
HO2S heater power circuit is open (test O2S fuse in fuse block)
HO2S heater element is damaged or has failed
PCM has failed
Monitor Information:

General Motors

OBD II Monitor Type: O2S HTR1

HO2S Heater Overview (1995-2000 Models)

The HO2S contains a heater that is necessary in order to quickly warm the sensor to operating temperature. The heater also maintains the operating temperature during extended idle conditions. The HO2S needs to be at a high temperature in order to produce a voltage. When the HO2S reaches operating temperature, the control module monitors the HO2S bias, or reference, voltage.The PCM monitors the HO2S signal voltage for Closed Loop fuel control. During normal Closed Loop fuel control operation, the PCM will add fuel (i.e., enrich the air/fuel mixture) when the HO2S detects the exhaust content is lean). The PCM will subtract fuel (i.e., it will drive the air/fuel mixture in a lean direction) when the HO2S detects the exhaust content is too rich.
HO2S Configuration Graphics

The PCM determines if the HO2S heater circuit is functioning properly by monitoring the time required for the HO2S to reach a normal operating temperature. The PCM sets a trouble code when it fails to detect sufficient HO2S voltage transitions above and below the bias range within a specified amount of time.

HO2S Heater Overview (2000-2003 Models)

The heated oxygen sensor (HO2S) heater is used to reduce the time the Oxygen sensor takes to become active. The PCM controls the HO2S heaters using a High Side driver, two Low Side drivers, and a Current Monitor driver. The Current Monitor driver tests the condition of the heaters. The High Side driver provides the Bank 1 Sensor�1 heater with ignition voltage. A fused ignition feed is used to provide system power to the Bank�1 Sensor�2 and Bank�2 Sensor�1 with ignition voltage. The Bank 1 Sensor�1 and Bank�2 Sensor�1 are connected to ground through one of the Low Side drivers. The Bank 1 Sensor�2 is connected to ground through a separate Low Side driver.
HO2S Heater Monitor Operation (2000-2003 Models)

With the engine running, the PCM turns �on� the High side and Low side drivers in order to warmup the oxygen sensors. When the proper conditions are present, the PCM keeps the High side driver "on", turns "on" the Current Monitor driver, and then turns �off� the Warmup driver. This action allows the PCM to record the total current value for both of the Fuel Control heaters. If the test conditions remain stable, the PCM enters the second stage of the test. During this stage, the PCM keeps the Current Monitor "on", and turns "off" the High Side driver. This action allows the PCM to record a current value for the Bank 2 Sensor�1 heater circuit. The PCM subtracts the Bank�2 Sensor�1 current value from the total current value to determine the current value for Bank�1 Sensor�1 in order to determine if a fault is present in the heater.
DTC P0135, P0155 Description (1995-2000 Models)

This trouble code indicates the HO2S voltage remained at or near the bias voltage (300-600 mv) for a calibrated period of time.
DTC P0135, P0155 Description (2000-2003 Models)

This trouble code is set if the PCM detects a Bank�1 Sensor�1 current value outside the calibrated range, the trouble code is set.
DTC P0141, P0155, P0161 Description

The PCM tests the HO2S heater only after a cold engine startup. The PCM determines a cold startup based on the difference between the ECT sensor signal at the last key off, and the ECT sensor signal at the current key on period. When the HO2S voltage indicates a sufficiently active HO2S, the PCM looks at how much time has elapsed since the engine started. If the PCM determines too much time was required for the sensor to become active, this trouble code is set. The amount of time for the HO2S to reach a normal operating temperature is based on the ECT sensor signal at startup and the average airflow value since startup (i.e., more airflow and/or higher startup engine temperature at startup results in a shorter time to sensor activity).
Test Conditions

Because the code conditions for the HO2S Hear Monitor vary by year and engine, refer to the exact conditions required to run this test listed in the Trouble Code Details on the previous page.
Repair Verification Process:

The PCM will activate the MIL if it detects a problem during the HO2S Heater Monitor Test. Most HO2S Heater problems are considered a 2-trip fault. However, there are a few exceptions. The number of trips to set a particular trouble code is shown in the Trouble Code Details Information on the previous page.Freeze Frame Data The PCM stores the current operating conditions at the time a trouble code is set in a special portion of memory called Freeze Frame. This important information can be retrieved with an OBD II compatible Scan Tool, and can be used to help diagnose the cause of a trouble code related to this OBD II Monitor.HO2S Monitor Repair Verification An example of how to drive a vehicle to verify the repair of a trouble code related to the Heated Oxygen Sensor on these vehicle applications is shown in the Graphic below.
Repair Verification Graphic



DTC P0101, P0103, P0103, P0107, P0108, P0121, P0122, P0123, P0130-P0141, P0201-P0206, P0300, P0401-P0405, P0410, P0440-P0446, P0506, P0507, P1404 and P1441 not set, engine speed from 550-4000 rpm, ECT sensor from 68-230F, IAT sensor from 64-158F, MAF sensor at 2.8-150 gm/s, BARO sensor over 70 kPa, MAP sensor at 15-105 kPa, VSS under 82 mph, fuel level over 10%, and the PCM detected the Short Term fuel trim was more than 20% for 6 seconds.
Possible Causes:

Air leaks in intake manifold, exhaust pipes or exhaust manifold Fuel control sensor is out of calibration (ECT, IAT or MAF) Fuel component fault (fuel filter, fuel injector, low fuel pressure) HO2S element is contaminated, deteriorated or has failed
Monitor Information:

General Motors

OBD II Monitor Type: Fuel

Fuel System Monitor Overview

The Fuel System Monitor is a PCM diagnostic that monitors the Adaptive Fuel Control system. The PCM uses adaptive fuel tables that are continually updated and stored in keep alive memory (KAM) in order to compensate for wear and aging in Fuel system components.Once the PCM determines the correct test conditions and the enable criteria are met (ECT, IAT and MAF values in range and with closed loop enabled), the PCM uses its adaptive strategy to "learn" changes needed to correct a Fuel system that is biased either rich or lean. The PCM accomplishes this task by monitoring the Short Term and Long Term fuel trim values during closed loop operation.
Long and Short Term Fuel Trim

Short Term fuel trim is a PCM parameter identification (PID) used to indicate Short Term fuel adjustments. This parameter is expressed as a percentage and its range of authority is from -10% to +10%. Once the engine enters closed loop, if the PCM receives a HO2S signal that indicates the A/F mixture is richer than desired, it moves the SHRTFT command into a more negative range to correct for the rich condition.If the PCM detects the SHRTFT is adjusting for a rich condition for too long a time, the PCM will �learn� this fact, and move LONGFT into a negative range to compensate so that SHRTFT can return to a value close to 0%. Once a change occurs to LONGFT or SHRTFT, the PCM adds a correction factor to the injector pulsewidth calculation to adjust for any variations. If the change is too large, the PCM will detect a fault.Note: If a fuel injector or fuel pressure regulator is replaced, do a PCM Reset and then drive the vehicle through the Fuel System Monitor drive pattern to reset the Fuel Control table in the PCM.
Additional Help for Fuel Trim Trouble Codes

The Fuel Trim readings on a Scan Tool do not always indicate a problem by themselves. However, Fuel Trim readings can be a real asset when attempting to determine the cause of one of these trouble codes, and to determine "where to start testing" to find the cause of an Air/Fuel mixture problem or Fuel System control related fault (i.e., related to a fuel control sensor or solenoid that may have failed).One of the first steps is to determine if the PCM is in "control" of the fuel delivery system. There are several test methods that can be used to make this determination. If the PCM is not in "control" of the Fuel Delivery system, the information in the Fuel Trim Repair Table below can be used to help find the cause of a Fuel Trim problem.
Fuel Trim Repair Table


HO2S Signal Tailpipe Emissions Fuel Trim Value Logical First Step
Rich Input (high O2S voltage) Rich A/F Mixture PCM adding fuel (+ %) Check PCM power and ground circuits for faults
Rich Input (high O2S voltage) Rich A/F Mixture PCM subtracting fuel (- %) High fuel pressure, leaking injector(s), air intake is restricted, plugged exhaust (MAP sensor)
Rich Input (high O2S voltage) Lean A/F Mixture PCM adding fuel (+ %) Test result not logical as more than one fault is present!
Rich Input (high O2S voltage) Lean A/F Mixture PCM subtracting fuel (- %) HO2S is contaminated, or the HO2S Heater power circuit is shorted to the HO2S signal
Lean Input (low O2S voltage) Rich A/F Mixture PCM adding fuel (+ %) Exhaust leaks in the manifold or pipes, air injection leaks in front of the HO2S, or the HO2S assembly is contaminated or it has failed
Lean Input (low O2S voltage) Rich A/F Mixture PCM adding fuel (+ %) Test result not logical as more than one fault is present!
Lean Input (Low O2S voltage) Lean A/F Mixture PCM subtracting fuel (- %) Low fuel pressure, dirty fuel injectors, large vacuum leak, or contaminated MAF sensor
Lean Input (Low O2S voltage) Lean A/F Mixture PCM subtracting fuel (- %) Check PCM power and ground circuit for high resistance
Lean or Rich Input (i.e., a low or high O2S voltage) Lean or Rich A/F Mixture Short Term Fuel Trim at 0% Engine operating in Open Loop mode or in Limp-In mode - check for any stored trouble codes
Freeze Frame Data

The PCM stores the current engine operating conditions at the time a trouble code is set in a special portion of memory called Freeze Frame. This important information can help pinpoint the cause of trouble code. It can be retrieved with an OBD II compatible Scan Tool to help diagnose the problem.
Repair Verification Process:

An example of how to drive a vehicle to verify the repair of a trouble code related to the Fuel System Monitor on these vehicle applications is shown in the Graphic below.
Repair Verification Graphic


Copyright 2010 IEC. All Rights Reserved.
Portions 2012 Cengage Learning. All rights reserved. Used under license.
P0300Engine Misfire Detected
Conditions For Setting This Code:

DTC P0101-P0103, P0106-P0108, P0112-P0113, P0116-P0118, P0121-P0123, P0125, P0128, P0200, P0300, P0410-P0446, P0452-P0453, P1258, P1415-P1416 and P1441 not set, engine speed from 500-5850 rpm, ECT sensor from 19-248F, A/C Clutch and TP angle steady, EGR Test not active, DFCO and Torque Control "off", fuel level over 10%, and the PCM detected a crankshaft speed variation in two or more cylinders characteristic of a misfire condition. Note: If the misfire is severe, the MIL will flash on/off on the 1st trip!
Possible Causes:

Base engine mechanical fault that affects one or more cylinders
Fuel metering fault that affects more than one cylinder
EVAP system problem or the EVAP canister is fuel saturated
EGR valve is stuck open or the PCV system has a vacuum leak
Ignition system fault (a coil) that affects more than one cylinder
MAF sensor contamination (it can cause a very lean condition)
Monitor Information:

General Motors

OBD II Monitor Type: MISFIRE

Misfire Detection Monitor Overview

The Misfire Monitor is a PCM diagnostic that continuously monitors for engine misfire events under all engine positive load and speed conditions (accelerating, cruising and idling). The Misfire Monitor detects misfires caused by fuel, ignition or mechanical misfire conditions. If a misfire is detected, engine conditions present at the time of the fault are written to the Freeze Frame Data. These conditions overwrite existing data.
Misfire Monitor Operation

The Misfire Monitor is designed to measure the amount of power that each cylinder contributes to the engine. The amount of contribution is calculated based upon measurements determined by crankshaft acceleration (TDC of compression stroke to BTDC of the power stroke) for each cylinder.The PCM receives data from the Crankshaft Position (CKP) sensor that relates to the crankshaft angle in order to detect any signal variations that could indicate when a misfire condition is present in the engine. The PCM continuously checks for the correct ratio between the CKP and CMP pulses to detect a misfire condition during engine positive torque conditions (i.e., acceleration, cruise and idle speed). The CKP sensor is the example below is a magnetic pickup design that outputs an AC signal to the PCM.
CKP Sensor Graphic


Two Types of Misfire Conditions

There are two types of misfire conditions monitored - one that would damage a catalyst and one that would only affect tailpipe emissions. If either fault is detected, the PCM will store current engine operating conditions in Freeze Frame and set a Misfire related trouble code.
Catalyst Damaging Misfire (One-Trip Detection)

If the PCM detects a misfire that could result in damage to the Catalyst, a Catalyst Damaging Misfire code will be set and the MIL will flash once per second within 200 engine revolutions from the point where the misfire was detected. The MIL will stop flashing and remain "on" if the engine stops misfiring in a manner that could damage the catalyst.
High Emissions Misfire (Two-Trip Detection)

If a misfire is detected that is sufficient to cause the vehicle to fail a State Inspection or Inspection Maintenance (I/M) Test, the PCM will set a State Emissions Failure pending code. This fault is determined by identifying a misfire percentage that would cause a �durability demonstration vehicle� to fail an Inspection Maintenance Test. If the Misfire Monitor detects this fault for two consecutive trips with the engine at similar engine speed, load and temperature conditions, the PCM will turn on the MIL and set a code. The MIL is also activated if this type of misfire is detected under similar conditions for two non-consecutive trips of not more than 80 trips apart.
Misfire Monitor Test

To run the Misfire Monitor, start the engine and drive at idle speed and then at Cruise (a VSS signal must be present). It may be necessary to drive the vehicle at highway speeds to test the system.If the Misfire Monitor detects a fault that could damage the Catalyst, it is a One-Trip Monitor. If it detects a fault that could cause the tailpipe emissions to fail the FTP standard, it is a Two-Trip Monitor (i.e., it requires that the test fail for two consecutive trips to activate the MIL).
Possible Causes of an Engine Misfire

* Air Intake system restrictions or a restriction in the Exhaust system * Base engine mechanical faults (Valve train faults, excessive carbon buildup, low compression) * EGR system problems (i.e., the valve is sticking, stuck partially open or closed) * Fuel injector connectors or wiring that are damaged * Fuel injector that is contaminated, dirty or damaged. * Vehicle driven while low on fuel, or it was run completely out of fuel
Repair Verification Process:

An example of how to drive a vehicle to verify the repair of a trouble code related to the Misfire Monitor on these vehicle applications is shown in the Graphic below.
Repair Verification Graphic


Copyright 2010 IEC. All Rights Reserved.
Portions 2012 Cengage Learning. All rights reserved. Used under license.



Freeze Frame Information

Parameter Description Results
DTC for which Freeze Frame was Stored P0301
Fuel System 1 Status Closed Loop
Fuel System 2 Status Closed Loop
Calculated LOAD Value 4.31 %
Engine Coolant Temp 122.00 F
Short Term Fuel Trim - Bank 1 28.13 %
Long Term Fuel Trim - Bank 1 0.00 %
Short Term Fuel Trim - Bank 2 27.34 %
Long Term Fuel Trim - Bank 2 0.00 %
Intake Manifold Absolute Pressure 13.62 inHg
Engine RPM 823.00 rpm
Vehicle Speed Sensor 0.00 mph
Air Flow Rate Mass Air Flow Sensor 1.31 lb/min
Absolute Throttle Position 0.00 %

Monitor Status

Monitor Name Monitor Icon Status
MIL (Check Engine Light) OFF
Misfire Monitoring Complete
Fuel System Monitoring Complete
Comprehensive Component Monitoring Complete
Catalyst Monitoring Not complete
Heated Catalyst Monitoring Not Supported
Evaporative System Monitoring Not Supported
NMHC Monitoring Not Supported
NOxAdsorber Monitoring Not Supported
Secondary Air System Monitoring Not Supported
Oxygen Sensor Monitoring Not complete
Oxygen Sensor Heater Monitoring Not complete
EGR System Monitoring Complete
Boost Pressure System Monitoring Not Supported
Exhaust Gas Sensor Monitoring Not Supported
PM Filter Monitoring Not Supported
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Wine
[/img]Thanks
Rich
 
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#12
Ha, did you post this for our benefit or yours?

Try and will be brief about the problems I found in these things, no such thing as finding just one problem, several hundred is more like it.

BCM, PCM, instrument cluster, cold corroded solder joints, every switch made with bare copper contacts that turn green and dried up grease on them. Insulation displacement connectors, where a tiny brass connector is suppose to reliable contact with unplated low strand copper wire that also turns green. Ever hear of a copper oxide rectifier? Has hundred of these. Poor grounds, corroded fuse panels.

With that 8 strand unplated wire in cheap plastic insulation, that becomes brittle,will break into two pieces between the body trunk or door. Arced relay contacts is another intermittent type problem, and if the fuel pump does not receive full battery voltage, will burn up. Current actually skyrockets with a lower voltage in a universal motor. Just some of the things.
 
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#13
Nawh just my benefit i am down to one car and have to spend all day running people to work and school. I have put a fuel pressure regulator in and now have 30 lbs pressure at the the rail. Runs a little better still not right. Looks like i need a new fuel pump.
the haynes manual only talks about getting to it through the trunk. do you know if ill have to drop the tank to do this. It seems like most of these codes cascade from low fuel pressure.
thanks
Rich
 
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#14
As I recall, if I am not totally losing my mind, 35 psi is the nominal fuel pump pressure on these things. GM as been rather inconsistent in providing a fuel pump access plate. Remove the rear seat and look, if not, you have to drop the tank.

Starting at the battery, can drop a little voltage through the fuse panel, more at the ignition switch, even more at the fuel pump relay contacts. Measured as much as a 3 volt drop. Pump normally draws about 4 amps, and can draw 6-7 amps with these extra voltage drops. Really runs hot and burns up the brushes.
 

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#15
OK, NickD, please explain this one:

"Starting at the battery, can drop a little voltage through the fuse panel, more at the ignition switch, even more at the fuel pump relay contacts. Measured as much as a 3 volt drop. Pump normally draws about 4 amps, and can draw 6-7 amps with these extra voltage drops. Really runs hot and burns up the brushes."