Hesitating/missing problem

[BENSGTIR]

Hi all, got a strange problem with my R which ive had for a while now and tryed so many things tyring to cure it, but its STILL there.

When the car is cold it drives fine, get it up to temp and it plays up like mad, starts to hold back before boost and seems like its running on 3 cylinders.
Ive tryed the fault code check so many times and comes up clear every time, ive swoped the afm, injector module, complete distribitor, module behind the dizzy (not sure what it is called), new hks plugs, new leads, dizzy cap is fine, fuel filter is ok and a have a new walbro fuel pump on too. Ive took the car today to be plugged on a proper diognostic machine to see if that picked anything up (as you guessed, no it didnt).

Any ideas? it is much appreciated as its doing my tits in now.

Thanks. Ben.

 

[another sunny]

I have just cured my similar problem, my FMIC top hard pipe had a crack where the bracket bolts to the head. Probably not the same problem that you have but worth a check for the 2 seconds it takes.
Good luck

 

[Braveheart]

If you have no fault code, changed all the ignition components and your sure the fueling is ok then it could be as above, a vacuum leak.
Keep us posted and good luck!

 

[Dooie Pop Pop]

coil, leads or ignition amplifier.

 

[KF79GTIR]

Are you sure its not running on 3 cylinders all the time you could try letting it warm up for 5 mins pull your dipstick out about an inch and give it some revs if you see smoke pour out the dipstick hole then it has either blown a piston or the rings. I do hope its not for your sake

 

[antgtir]

A vacuum leak is one of the main culprits, i have a similar prob but not as aggressive as you have described. I was chatting to a "tuners" last weekend and they suggested i check the BOV as if the spring is worn then it could be letting additional un metered air into the combustion process and so throw out the initial AFM reading sent to the ECU.

I still have my OE re circ valve so i will be trying this possibility over the weekend probably. A cracked hard pipe as suggested is a good possibility to.

Ant.

 

[BENSGTIR]

Thanks for the replys plp, its def not running on 3 cylinders all the time, ive also changed the coil pack, and ignition amplifier. im 99% sure theres no air leak, ive tyred blanking my hks off a few times just for a change off sound so id say its not that either. Ive got a friend whos going to borrow me a det sensor and an ecu, i`ll try them and keep you posted, thanks.

 

[Fusion Ed]

Water temp sensor? Car starts fine heats up ecu still running in cold for what ever reason so is rich and lumpy...?

 

[another sunny]

Where is the water temp sensor?

 

[antgtir]

I was once told by a wise man that if the top end of the engine is noisy i.e. requires shimming up the noise from this can effect the knock / det sensor which in turn can tell the ECU to retard the ignition making the car feel hesitent / holding back etc, as you say all you can do is try and see what happens, but defo keep us informed.

Ant.

 

[Fusion Ed]

That's true, if its noisy during the parts where the knock sensor is active. Just thought no one has mentioned to do a fault code check. That should really be the next thing.

 

[Granite-GTiR]

Hi all, got a strange problem with my R which ive had for a while now and tryed so many things tyring to cure it, but its STILL there.

When the car is cold it drives fine, get it up to temp and it plays up like mad, starts to hold back before boost and seems like its running on 3 cylinders.
Ive tryed the fault code check so many times and comes up clear every time, ive swoped the afm, injector module, complete distribitor, module behind the dizzy (not sure what it is called), new hks plugs, new leads, dizzy cap is fine, fuel filter is ok and a have a new walbro fuel pump on too. Ive took the car today to be plugged on a proper diognostic machine to see if that picked anything up (as you guessed, no it didnt).

Any ideas? it is much appreciated as its doing my tits in now.

Thanks. Ben.

Hi Ben, i have just sorted a problem very similar to this and it pi$$ed me off for ages! Have a look at this -

http://www.gtiroc.com/forums/showthread.php?t=30681&highlight=high+idle

My problem was number 7 in the list, its worth a try. Good luck.

 

[BENSGTIR]

Thanks plp, ive checked the blanking thingi bobs and they are all on tight, ive ordered a new coolent sensor too, should be here tomoz, i`ll try that too.

 

[BENSGTIR]

Well, all seems good, put a new coolent sensor on and another det sensor, and whooopie, it hasnt played up since, (fingers crossed) its sorted.

 

[Granite-GTiR]

Glad to here that the problem seems to be solved. Mines still giving me grief...runs like sh1t once its warmed up! I'll have to try replacing the coolant and det sensor on mine.