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weird cold start

GarageJunks

By GarageJunks,
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GarageJunks Contributor

GarageJunks

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I've searched on this site for my problem and there seem to be similar symptoms around but not exactly the ones I’m experiencing.

When I cold start 75% of the time my car will stay at around 400RPM like it’s about to stall. If I ever so slightly touch the accelerator the car will bring itself up to the normal 1500RPM.

In addition I’ve seen a lot of problems with people's cars missing at 5000 RPM. My car doesn't miss at 5000RPM but looses power after 6000RPM. I am getting full boost fine at 5000 RPM.

My cars only mods are pod filter, exhaust and large intercooler. The car is not running an aftermarket boost controller, so it’s just standard boost.

I'm going to take this car to a mechanic but wondered if there was something I could do myself to save money.

I have completed an ECU diag, changed spark plugs, fuel filter, cleaned airflow meter to no avail.

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GarageJunks Contributor

GarageJunks

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Thanks. I've got a feeling it might be some kind of injector issue, but im only guessing.

Ask the Mechanic to checkout if its one of these 2 problems.

Possible Leaking injector..

Aire in your fuel line.

As i have a similar problem on a cold start. let me know how it goes..

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GarageJunks Contributor

GarageJunks

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Thanks for your reply. I'm not to sure what TPS or AAC stands for. When i cold start the car is strugles to get above 400 RPM, but if you leave it long enough it suddenly jumps to 1500 RPM... If i slightly push the accelerator pedal this causes the car to jump to 1500 RPM also...

So it sounds like both idles are set where they should be.

Sorry for appearing car 'stupid'.

hv u check the TPS, thorttle & your Fast idle ctrl? there are 2 plugs on the AAC value.. the upper 1 is fast idle & the other 1 is normal idle.
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Jolinator Proficient

Jolinator

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hey mate, you see in that photo that block of alloy with the gaskit inbetween it and the manifold, well that alloy block is the aac valve assembly, there is a a few bolts holding it on, unbolt them it wall fall strait off, once you do this you will see the little valve on the inside, give it a good blast with carb cleaner,

sorry about the engrish,

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GarageJunks Contributor

GarageJunks

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Thanks, I'll give it a go...

hey mate, you see in that photo that block of alloy with the gaskit inbetween it and the manifold, well that alloy block is the aac valve assembly, there is a a few bolts holding it on, unbolt them it wall fall strait off, once you do this you will see the little valve on the inside, give it a good blast with carb cleaner,

sorry about the engrish,

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