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Hey all! for the past couple months I've been experiencing rough idle only on start up. It's weird cos it only does it on a warm start, say if I were to turn off the car then start it up 20 minutes later. The idle fluctuates so much to the point of the car almost stalling on me which is driving me crazy :huh: but as soon as I take off and go for a drive its fine. I'll go through and list everything that I've done to try solve the problem.

. cleaned aac valve

. swapped afm with a known working one

. replaced o2 sensor

. checked spark plugs and coil packs

. replaced almost every hose in the damn car so it can't possibly be a hose

. took off my atmo bov and put the stock one back on.

. adjusted the idle (it sits at about 750-800rpm but still has the same problem)

One of the only things I haven't replaced is the fuel pump or injectors. Could it have something to do with the fuel delivery? If someone has experienced this before please help me lol

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My guess would be that one of your injectors is sticking. Maybe run some injector cleaner through your car you can get a bottle from super cheap auto for 5 dollars. I don't think its the pump because if it was the pump you car probably would stall. Could also be the fuel filter. I've also heard of similar issue with people who have a leak in their manifolds, but I don't think this your problem since it goes away when the car warms up. I'd pull out the injectors and give them a good clean.

My guess would be that one of your injectors is sticking. Maybe run some injector cleaner through your car you can get a bottle from super cheap auto for 5 dollars. I don't think its the pump because if it was the pump you car probably would stall. Could also be the fuel filter. I've also heard of similar issue with people who have a leak in their manifolds, but I don't think this your problem since it goes away when the car warms up. I'd pull out the injectors and give them a good clean.

It shouldn't be the fuel filter as I replaced that about a month ago. But I'll try get the injectors cleaned. Thanks for that man!

my car does the same thing. i was presuming it is a sensor that isnt working until a certain heat. i notice it happens once the autochoke turns off. as far as i know mine has stock ecu. only mods are filter, exhaust, intercooler, t piece. i have used injector cleaners. cleaned maf.

Seems as though a bottle of injector cleaner has fixed my idle issues! :D Just before i filled up today I added half a bottle of the cleaner in and filled up with mobil 8000 instead of the usual vortex98 that I run my car with. So i'm not too sure if it was a combination of the cleaner and different fuel but it's fixed my problem.

Seems as though a bottle of injector cleaner has fixed my idle issues! :D Just before i filled up today I added half a bottle of the cleaner in and filled up with mobil 8000 instead of the usual vortex98 that I run my car with. So i'm not too sure if it was a combination of the cleaner and different fuel but it's fixed my problem.

Yeah looks like your injectors were getting a bit dirty and sticky.

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