Idle Issue.

[89ghost]

I need thoughts on why my car is running like shit at idle or at least when it comes down from idle. When driveing the car is sputtering not backfireing. Also when driving and i push the clutch in the cars rpms go way down and dies. sometimes the rpms go up,down,up,down then idles ok. By the car is a 89 gt. Any suggestions would be great. Thanks

[89ghost]

It does have 24lbs injectors with 70mil throttlebody and 70mil massair calibrated for 24lbs

[Snatch Napkin]

What other mods does the car have?

[89ghost]

93 cobra heads with roller rockers that came on the 93 cobra. a comp u cam specs are same as ford raceing e303 cam and 97 explorer intake.

[Josh.0]

Needs a tune up?

[89ghost]

motors only got 10 miles on it.

[Texasmustang]

Do you have the firing order right.

[Josh.0]

yea ^^^ thats next

[89ghost]

I took it to a shop about a week ago cause i heard a vacuum leak. They couldent find it at all either so they adjusted the timeing and it went away (weird i know) now it runs like shit and falls on its ass! just replaced the idle air control and its doing the same thing.

[Snatch Napkin]

Any reason why you didn't turn right back around and ask them why your car runs like ass?



There are a shit ton of variables here as to why it runs horrible. Internet diagnosing will not be suitable in this situation. Your best bet is to take it to a reputable shop. The last one most likely is not.

[Josh.0]

check the timing then?

[89ghost]

fireing order is 1-3-7-2-6-5-4-8. and its right. im not good at timeing its my first mustang thats efi.

[89ghost]

well the car ran fine that day but it still had the sputter. now it's running worse.

[Josh.0]

check your cap and rotor. does it happen all the time or just sometimes?

[TENGRAM]

Check the Codes