Hard start on 2004 Buick Park Ave

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
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OK, I got it... this is *only* a starting problem. When you say "it won't turn over", you mean it won't fire, but it always cranks, correct?

You really need to use live-data to get this effort back on track. Although the fuel pressure was the most likely culprit, but seems OK, other suspects are the ECT sensor, TP sensor, and IAC valve. Those can be checked with just a multimeter, but the live-data will make it much quicker and easier.
 

MattCantRap

Newbie
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Oct 11, 2019
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Yes that is true. It always cranks but doesn’t always start. What do you mean when you say live data?
 

nickb2

Wrench. Diagnostic Tech.
Joined
Nov 22, 2008
Messages
11,025
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Location
St-Hyacinthe, Quebec, Canada
5 psi off is enough to cause problems. You really want 53 or more. It should not drop below that. Try removing the vac line to regulator, does FP rise in psi?.

If you have a phone or laptop, something cheap like this should get you good live data https://www.amazon.ca/ELM327-Bluetooth-Diagnostic-Interface-Scanner/dp/B07T4WFJ4M/ref=sr_1_12?crid=1ADHTP9XQPUQL&keywords=elm327+bluetooth&qid=1571261985&s=automotive&sprefix=elm+327,automotive,163&sr=1-12

But if you are willing to pay a few bucks more for some bi directional as well, this unit is sweet and cheap. Will pay for itself in no time on this car. It is like having a OEM tech 2 on your laptop. https://www.amazon.ca/VXDIAG-Tech2Win-Diagnostic-Programming-System/dp/B06XDHF3XX?th=1
 

grcauto

Hero Member
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May 29, 2014
Messages
706
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I checked my fuel pressure and when I primed the pump it was 52, do you mean the fuel pressure measurements from when the car is running?
If that's the vortek engine you will want 55psi min. Anything less can cause problems.
 

MattCantRap

Newbie
Joined
Oct 11, 2019
Messages
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It was my ICM and My CAM sensor intermittently malfunctioning. Thank you all for your help
 
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