2008 Chevy Impala 3.5 Hard Starting When Cold

nickb2

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Gums up all sorts of things, premature wear. Stupid. NickD has been writing about this way more than me. I jest and try to push the guys to come here and learn the basics of modern cars, and that can be done even with a raspberry pie if you want. Knowledge is power, and tech is now the way. Embrace it or fall behind.
 

montego_gto

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You need a new mechanic. Starter is working. With engine cold I would use the scan tool to look at the IAT and ECT temperature sensors. They should read real close to each other.
grcauto,
Before cranking the IAT was 54 and ECT was 52. In one minute the IAT was 54 and ECT was 79. At 2 minutes the IAT was 54 and ECT was 97. At 3 minutes the IAT was 55 and ECT was 111. 4 minutes IAT was 55 and ECT was 124.
fuel pressure was 58 when I turned the key before crank and it settled at 55. It stayed at 55-56 during crank and rose to 59 and stayed there while it ran for the 4-5 minutes.
I did not look at the MAP while cranking. Sorry. I shut it off at the 5 minute mark, wrote my response and then just now went back to the MAP. Key on and no run it is 29. At crank it drops to 10 and settles in at 11. It started fine, which I expected, since it had been just running for 5 minutes.
ECT is now 145 and IAT is 59.
 

montego_gto

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If I am reading this thread right, you are using a low latency scanner/code/live data thing.

Have you tried elm 327 simple devices, they communicate live data faster for a fraction of cost, but you need to learn how to navigate. I can help with that.
nickb2,
I’m using a Zurich ZR11.
nick
 

montego_gto

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Useless. Throwing parts. I get so pissed offed when I read threads such as these.


I sadly, 100% agree with above.
i was totally skeptical when the GM mechanic told me his thoughts on the starter.
Since it was less than 1 year old, I turned it in on a warranty claim. I explained it to the local parts house what was going on and they told me it didn’t directly affect their store pocketbook so they’d warranty it regardless if it fixed the issue or not. They’re nice guys.
nick
 

montego_gto

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Nickb2,
My wife drove the first 140,000 miles where she fueled up with E10 regularly.
I refuse to run any so the only corn alcohol that gets in the car now is what is still in the dispenser assembly when I begin fueling up with non-ethanol fuel. Yes it costs me a bit more at fuel-up but I’ve seen too many alcohol fuel-related issues.
Nick
 

montego_gto

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Cool, you need those once in a while/

Ok zurich. Well that can only get you so far. Do you have an intel laptop, I don't even car if it is a pentium 1st gen, I have galore software options to get great baud rates.
All I’ve got is a new work computer. Pentium i5 I think.
 

nickb2

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I5 is awesome. You can do real sweet things with that processor.

In the tech dept.

Are you willing to spend 14 or so dollars for a dongle?
 

nickb2

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even a dual core will drive a snappy baud rate, will need upgrades and software to get there, but you could achieve the same thing on a tablette.

The trick is reading the live data as it flies, not easy on a zurich thing of a ma jig. No bi direcxtiobal to help, iless tool except for getting a OBD2 code, cant get manufactuer with that. Just think about it, google all you see with my threads here, aside from stupid tunes, what do I espouse, software, and hardware, only to way to fix these things and communicate with them is to understand them.
 

montego_gto

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This ZR11 is the first reader I’ve used with the ability to graph while the vehicle is running.
There’s nothing in the instructions about how fast it is.
 

nickb2

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Mode six is where you see the pcm thinking the algrorythm, and passing or failing in the execute cmd .

This is where you get real good at diagnostics.
;)
 
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