Car starts then dies on a cold start. i have to give it gas to keep it going, when its a little warmer the idle bounces from 500 to 1500, then when its fully warm its alright.

 

maybe adjust your timing and idle. I had the same problem when my idle was low. But lately every now and then when I start my car, it dies and I have to deflood the engine. Happened to me this afternoon on a sunny *** day in california. Still trying to figure out what's the problem. Previous owner said he replaced the fuel pump with a walbro 255

 

Do you have an Adjustable Fuel Pressure regulator with that 255? Almost a guarantee that your fuel pressure will be to high If you dont. The ecu has no way of checking the fuel pressure so it will always pulse to much fuel and will always try to lean with the inaccurate o2 and IPW. all that makes for one finicky start especially if the pressure is too high for the ecu to compensate via ipw.

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still having the same problem. some input would be nice. if someone could show me a link to something that would help that would be grand. like how to adjust the bac to and what it should be set at.

 

Year and model perhaps?

 

88 gxl

 

have you tried anything already suggested? or just asking for more help with no feedback?

 

+1 two way street this is.

Since it's S4, you can check the troubleshooting section in Chapter 4 of the FSM for cold idle issues...

 

people tell me to do things like adjust the bac valve without explaining how its done or what it should be set at. its usually smart *** remarks that try to condesend me.

 

An S4 na BAC is not adjustable. Secondly, does the car still have the fast idle mechanism still in working order which would allow the engine to slowly lower its rpm? And the advanced search feature, when used properly, should be able to keep you busy w/an endless supply of information.

 

If they suggest you do something but do not tell you how,that is because it is already documented in threads that can be found rather easily.
Assuming that if you just type up anything and get help instantaneously is not going to happen.
Your Car,your problem.That is why the Answers are documented.So you can find them yourself and not have to rely on others holding your hand and directly answering your every thread.,
Repetition of frequently questions causes some hostility in answers so please take the Advice to search before you ask.

Even your car series was left out,so how is anyone able to help you when you do not provide the info to help?

2 things come to mind..check your water thermo sensor,Thermo wax and adjust your TPS.
HOW?..I'm sure you'll find the threads on how to do that.

I just typed in "Bouncing idle" and got 10 pages of info.

 

yes. and the cold start valve. which usually works untill it hits where its supposed to idle, then it cuts out. ive adjusted the tps, but i have to adjust it about everyday, so its probably faulty. sometimes its dying and is bouncing and it wants to hold the idle, then dies out. i feel like its not getting the correct amount of fuel or air on the start up.

 

If the rpm is above a certain threshold the timing advances a bit and when under a certain threshold the timing changes back. You could be going back and forth w/the timing setting causing the fluctuations. Secondly, the TPS G/R wire should be set to 1 volt w/the key to on and the engine as hot as it can possibly get (this is not achieved by just starting the car as it takes at least a twenty minute drive).

 

yes. today was hot as **** and i drove for well over an hour before adjusting it again. ive noticed that i can just push the sensor toword the throttle adjustment screw a little bit and that puts its back at the correct spec. is having doing this ok, or should it only be adjusted with the screw? because i cant adjust it to what its supposed to be at with only the screw.

 

The adjustment screw is just that, as there is no other way to adjust it in a normal situation. The bracket should not have to be bent to adjust the TPS. Are you sure you are using the correct screw? It's one inch long and encased in a spring. Also, if the fast idle cam has not released properly then it prevents the TPS from being set correctly. Lastly, reading the TPS from one day to another needs to be done when the engine is again at full operating temp as opposed to one temp one day and a different temp another.

 

where is the fast idle cam and how do you know if its been released properly?
im a mere noob please explain

and im sure im useing the correct screw

 

you havent learned anything from this thread yet

 

ive learned i need tools

 

That is most certainly a start......

 

So for a tii swap would you also need a fpr if using a 255 or only for an n/a?

 

but i have to push it tword the screw to get it at the correct adjustment. the screw doesnt have enough thread to get it where it needs to be. do i just need a new tps or should i get a new bracket to try and hold it in place better

 

Again, it's not normal to have to bend the bracket to get it within spec. There is nothing about bending brackets contained within the FSM. When the car is warmed up and idling steady what is the rpm at?

 

i dont really bend anything, just pushing the sensor up against the adjustment screw more to get it in spec.i have it at 750. but when i first start it its anywhere from 1500 to 2000 until i drive it for a little bit. theres also the occasional bounce when i first start it. but after ive been driving it for a while its normal. thats why when ever i take it to someone they just go "oh, this car is fine!".

 

How can you push the TPS towards the throttle linkage w/o bending it? If you press it closer and let go and it reverts to the same position then pressing it towards the linkage serves no purpose even if it doesn't bend the bracket. You might want to try loosening the bracket bolts and see if you can slide the TPS a bit to its right.

 

i dont even know what you mean by bending it, but thats what im doing, is sliding it toward the right, toward the screw.