Hey all, I'm having an odd problem. I have an 05 Monte LS with a 3800 in it. My problem is that intermittantly when I go to start the car, it will crank but it won't start unless you hit the gas. It doesn't do it always but enough that it's getting to be an annoyance. I brought it to the dealership, which tells me they can't duplicate the problem. I have noticed, that every now and then when it does start without giving it gas, the idle bounces a bit low and the engine shakes, before jumping back up to normal idling. Any ideas?

-Anthony

 

An LS with a 3800?... I didn't know they did that.

Intermitent problems suck!.

Sounds like a fuel delivery problem.


Tj

 

Stop intermittently not giving it gas

 

from what your describing to me

take it in and have them due a fule presure test on it and find out if it is giving the right presure. sounds liek the fule pump might be gettign weak. the other thing it could be is a filter pluged slightly.

there are several thigns it might be but honestly i would also start to check for leaks around the fule delivery system as a leak with them will cause it to suck air in to the fule line on start up.

im thining that it dose this after it has sat for a few min. weather it is hot or cold. the dealer will not ever figure this out till has to be done every time as they dont baby sit the car or attempt to drive like you . they hook them up and see if there is a code and got with what is said on a screen . or they attempt it for a short tiem and due to the fact they have so many cars comming it they just dont have time to figure it out.

Also if you happen tog et a bad mech., they wont even try to figure it out. (i have a shop full of them here)

 

Sounds more electronic to me, maybe the TPS (throttle position sensor)

The reason I think this is:

Intermittent.

Won’t crank until you tap the gas

Rough idle after start up more than likely when you relax on the gas pedal.

 

take your engine cover off and locate the fuel rail. easy enough. there is a vaccum line coming off the rail. that line controls your fuel pressure regulator, which regulates your fuel pressure. take the vac line off and check for the pressence of fuel in the line. if there is you will need a new one wich it sounds like you should have enough warranty left.

 

[sm=interesting.gif]

Chevy, has this been a pretty common problem with these? For those of us that have no warranty left what do they run $$$...

 

I did notice one thing. The hardstart problem began after I changed the stock air filter, with a Fram replacement OEM. Perhaps thats the problem?

 

sorry ive been busy. yes they have been a problem. they actually had a recall out on them. you would have to talk to your dealer about it if its involved or not. $$ im not sure. they should not be too bad i wouldnt think.

 

I just got a check engine light today, so I called "OnStar" for the one the road diagnosis. Turns out it is the "Idle Speed System Control". I don't know what this is but I'm willing to bet this is whats causing my problem, since the car idles low when it first starts up. Any help on this guys?

-Anthony