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Fuel And Idle Problems

vitz_n1

By vitz_n1,
in Engines & Forced Induction

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vitz_n1 Community Regular

vitz_n1

Posted
Posted

hey guys, just got a few q's about some issues im having.

The issue is with start up/idle. When i start my car i always turn the ignition on and wait for the fuel pump to prime, but when i do this, just before its primed it starts to make a bubbling noise. sounds like there is air in the fuel lines or something. Then when i start the car i have to give it a bit of throttle to start it. Thennn on idle she has a miss, its REAL bad when its cold, nearly stalls sometimes and gets better as she warms up, but never stops. When i drive its fine and dosn't miss a beat. I am also getting shocking mileage from a tank.... about 300 - 340 km per tank. And to top it off i think it leaning out bad after about 6000rpm :S

Only fuel system mods i have are bosch in tank pump and safc II.

Anyway, im taking the car down to the dyno on tuesday to have it tuned and looked over but i just wanna know if there is a solution to this as id rather have it fixed before the dyno rather than going there and then having to fix it and go back.....

Cheers

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tacker Mentor

tacker

Posted
Posted

could be a duff plug or 2. Did you have the car tuned after fitting bigger fuel pump as it may well have stuffed the old tune. I did see a lower AFR when i put new fuel pumps in and if your old pumps was a little tired evenmore so, and if your running rich you may have fouled a plug hence why it idles a bit rough until it warms up.

Then again i could be wrong as i seem to be good at that. :-)

vitz_n1 Community Regular

vitz_n1

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  • Author
Posted

i have not had my injectors looked at, nor do i know the age of the fuel pump as i purchased the car with it. i dont think its sparkies as i changed them and that did nothing.

Also, would gtr injectors run on a standard gtst ecu? when i purchased the car it had a re-mapped ecu and the guy i bought it off said he thinks it has gtr injectors. i later changed to a standard computer thinking that it may have been a shit tune, but it was exactly the same so i assumed they were standard.... if they are gtr ones that may be it.... :S

mad082 Grand Master

mad082

Posted
Posted

i get that bubbling noise in the missus pulsar, and it starts perfectly, so i don't think it would be that. it could be a clogged injector which isn't shutting off 100% so richening the mixtures up. otherwise try cleaning the aac and iac valves to make sure it isn't them.

vitz_n1 Community Regular

vitz_n1

Posted
  • Author
Posted

Ok! I've now had the car down at the dyno and it is running really lean everywhere. initially it was thought to be the air flow meter. i replaced that but it didnt really change anything.

-Tacker- The injectors have red tops

im now backing the injector theory and possibly just bad fuel pressure. is there a way to test fuel pressure and the fuel pressure reg?

Also mad082 how do i clean the aac and iac valves? and where is the iac valve located?

Cheers

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