Xu10j4 Engine Cutting Out And Will Not Rev

[gav_mi16 0]

I will try and describe this as best as I can and would appreciate any help chaps as i'm lost on this now.

The engine takes a lot of cranking and spluttering before it will start but as soon as it does it will sit at a very steady nice idle.

If you increase the engine speed gently it will by in large be ok up to around the 4k mark before the problems start (but not always). If you increase the engine speed more quickly (or under load whilst driving, or foot to the floor) then the engine objects.

It feels like the engine is cutting out and recovering within seconds.

 

For example, hold foot steady on accelerator and the engine will increase rpm smoothly and quickly, cut out then increase again to more or less the same rpm, this is a constant cycle, and it does this quickly (almost like an F1 car revving up and down) this will not stop until I let go of the accelerator or back off a bit.

 

I've checked over any obvious loose connections or loose pipes. Changed, ECU, Coil packs, coil pack leads, plugs and ICV.

It's the XU10J4 ACAV system.

 

Basically the car is not drivable as it will kangaroo violently. Any help appreciated.

Edited October 2, 2010 by gav_mi16

[gav_mi16 0]

Would it help to video the problem?

[kyepan 291]

my gut instinct tells me that it's having problems sensing the air flow, or load, If you had an AFM you could back probe it with a volt meter to double check. IIRC, those engines don't have an afm. Perhaps back probe the throttle position sensor to check it is varying the voltage in a linear fashion..

 

I would also say it could be an air leak, but this would be more likely to affect idle but not WOT high revs, and you've checked.

 

J

[gav_mi16 0]

Thanks for the reply.

You are right that there is no AFM on these, but the TPS is interesting and i'll investigate that.

As for the air leak, although Ive checked I don't think it can be the problem, the engine cutting off is much more "electronic" if you know what I mean and the engine fault light comes on too which I forgot to mension before.

Would the ignition amps (there are two on this) cause this sort of problem?

[kyepan 291]

Would the ignition amps (there are two on this) cause this sort of problem?

possibly but they usually exhibit symptoms when hot, and at higher revs / under high load..

 

i would not rule anything out.

 

J

[Alan_M 66 1 Cars]

Is this car the one in your signature?

 

205 GTi 2.0Mi16 with full 1.9Mi16 wiring and manifolds

 

If so, how are you running 1.9Mi16 wiring without an AFM?

[gav_mi16 0]

possibly but they usually exhibit symptoms when hot, and at higher revs / under high load..

 

i would not rule anything out.

 

J

 

I'm trying to get the diagnostic plug to work to see what faults are recorded as the engine light does come on intermittently when the fault occurs, but I can't get it to start the test.

Still to chesk the TPS as well. Incidentally the problem is worse when the engine hotter and under more throttle load but then again ive only driven it twice since the problem, not really drivable.

 

Is this car the one in your signature?

 

205 GTi 2.0Mi16 with full 1.9Mi16 wiring and manifolds

 

If so, how are you running 1.9Mi16 wiring without an AFM?

 

No its the standard ZX 16v which is the same as an S16

Edited October 4, 2010 by gav_mi16

[jackherer 543]

IIRC they have a MAP sensor in the ECU with a hose running to it? If so it is worth checking that for splits/leaks.

[welshpug 1,657]

They do indeed have a MAP sensor in the ecu, could also be an idle valve fault.

[gav_mi16 0]

Thanks for the info guys. I have checked the hose going to the CPU and indeed changed the CPU itself too, it was my first thought when the problem started. I have also changed the idle control valve and the problem still persists. Unfortunately I don't have any ignition amps spare so I will probably have to bight the bullet and buy a pair so at least I can eliminate them. I couldn't get the fault socket to give me any reading whatsoever, i'm wondering if i'm doing something wrong but I'm sure I'm not doing anything different to the last time I read the fault codes, so I cannot understand why its not working now.

[gav_mi16 0]

Strange indeed. Had a test run along a quiet long stretch. It seems to sometimes pull at full throttle all the way, and then other times it will object as if you've lost spark (ECU light comes on when the problems are there). Other times it will pull on full throttle but back off slightly and then t will do the same. I don't know what's up with it.

 

Here is a video of the problem if it helps anyone.

 

 

I am pushing then "HOLDING" the throttle and not dabbing it, the engine is revving up and down on its own until I let go. You can plainly see the problem. When the ECU light goes out its possible to gently accelerate up until about 4k rpm.

[CaptainK 11]

My first thought when I read this post was the MAP sensor / AFM. As your engine has a MAP sensor I'd checking the wiring to that and the electrical plug on it - and also the sensor itself.

 

I had this problem on my engine (GTi6) where it was a pain to start, and revving it would produce not much use and it sounded dreadful. Turned out I'd forgotten to reconnect the MAP sensor after installing a new inlet pipe.

 

The other issue I had when my engine kangaroed was with a problem with the lambda probe - the person who did my conversion forgot to setup the heater wires to the lambda, thus it stayed cold and when it switched to "closed loop / lambda control" it would go nuts. But I doubt this is your problem as when the engine first starts it doesn't use the lambda until the engine is warmed up.