Stalls at start up problem, please advise.

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Jul 3, 2005 | 06:11 AM

frank1

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Stalls at start up problem, please advise.

I have 4.9L 88 that stalls when its started only when the weather is hot, it goes thru this ritual every time the outside temp is hot, and the engine is first started. Sometimes 3 or 4 times before it will run and then I have to fan the gas pedal until it idles good. I checked codes and came up with a code 23 TPS. I replaced it and cleared the codes, and still have the same problems.

I have been searching high and low thru various threads and can't seem to find an answer.

When its cool or cold outside it starts the first time and runs great, no problems re-starting either.

I have so far cleaned the throttle body, replaced the IAC, and TPS. No luck!!!!!!!!!!!!!!!!!!!!!

Any additional suggestions would be greatly appreciated.

frank1

Last edited by frank1; Jul 3, 2005 at 06:25 AM.

Jul 4, 2005 | 07:11 AM

Tranzmaan

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From: Westmont N.J.

How does it run the rest of the time? I think the first thing I would check is the fuel pressure.

Jul 4, 2005 | 08:20 AM

frank1

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Once the truck finally starts and it runs a little its fine. It has a surge problem, but that works itself out after it runs a while too.

I thought about fuel pressure, but as I mentioned when its cold as in the winter it starts and runs perfectly, this is a summer time issue.

frank1

Jul 4, 2005 | 02:06 PM

Roushians

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From: Toronto, ON

Hey, I have a similar issue. When the truck is started cold (not run a while beforehand), it starts up nice and normal, and idles normal.
When the truck is started shortly after been running at normal temp for a while, it will GO NUTS - bucking and jerking, making a loud knocking sound from under the hood, etc. I have to gun the gas pedal to get it to get back to normal, it takes a second or two of almost full throttle then it revs way up (because of the open throttle), I let off and it idles normal. I have no freaking clue. I am taking my truck into the dealership for a full analysis/diagnosis soon and will get back to you

Jul 4, 2005 | 02:24 PM

oldhalftons

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From: Spokane WA

check you fuel pressure anyways, even if it is only a hot weather issue. Aging electric pumps can bind or run slow until cool fuel runs through them.

check all the vapor and fuel return system.

Jul 5, 2005 | 12:23 AM

frank1

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Thanks for the reply, now I have to figure out how to check the fuel pressure. Years ago it was disconnect a fuel line and crank the motor and watch the fuel get pumped into a coffee can. Wish it was that easy now.

frank1

Jul 5, 2005 | 02:04 PM

Roushians

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From: Toronto, ON

To check fuel pressure, you need to get a fuel pressure gauge and attach it to the 'shrader' valve (which is located on the fuel rail - i haven't found it on my truck's motor yet, but it's out in the wide open on my bro's 1990 jeep, right between cyl 3-4).

That's pretty much all i know about it, I haven't tried it myself yet, although I should! I just can't handle buying a $50 gauge that I'll only use once.