R19 16v rough idle and stalling during warmup

[Geronimo]

mmmm. Any ideas where to start? I still have one thing left to replace in the ignition system, the ignition module. I´ll get a new one on saturday. If that doesn´t help then I´ll guess it´s time to tear the electrical system apart

 

[Chris H]

I would have a look where it runs along the subframe then up on the join at the engien and box

 

[Geronimo]

I mesured my TPS today to see if it was adjusted right. Feed line gives 5,4 V, should be 5 V, right? So when arm is resting it gives 0,6 V instead of 0,2 V. Does that matter? Resistance is as it should be but voltage is higher.

 

[Chris H]

higher voltage means theres an issue somewhere, you'll probably find the alternator is overcharging so the whole system voltage will be higher, this isn't much of an issue as everything will be bumped up by the same amount. But if its not then you have an ecu issue.

 

[Geronimo]

higher voltage means theres an issue somewhere, you'll probably find the alternator is overcharging so the whole system voltage will be higher, this isn't much of an issue as everything will be bumped up by the same amount. But if its not then you have an ecu issue.

ECU I have 3 of and it´s the stalling issue appears with every one of them. But I havn´t mesured voltage with all 3 of them. I also trien to adjust everything correct on the throttlebody today. But! If I adjust idle to ~950 rpm without the ISV plugged in idle will raise to 2000 rpm whith ISV plugged in. Normal? According to the guide here idle should stay at 950 rpm when ISV is plugged back in. I have tried with different ISV´s but still same issue?

 

[Chris H]

your ICV is faulty if its doing that

 

[Geronimo]

your ICV is faulty if its doing that

All of them? Tried with 3 diffrent. Could be, cause non of them are new. Think that could have something to do with the car stalling?

 

[Chris H]

well if 3 of them are doing it and 3 ecus then like I said its a wiring fault

 

[Geronimo]

well if 3 of them are doing it and 3 ecus then like I said its a wiring fault

Lycky me then I have 3 of them too. Bought 2 sparepart cars so there is 3 of it all.

 

[Geronimo]

Today I got my hands on a "untouched" throttle house. With that throttlehouse and ISV from same car idle is fine and after changing all the relays in the enginge relay box and the ignition module car has not stalled yet. So far so good! But I don´t expect to much:?

 

[Geronimo]

So, update!

Still same problem. I have changed everything in the ignition system. All sensors are checked. PIN data test is done. Nothing strange there. Injectors, fuel rail, connectors are changed. And so on.

What happens now is that the car starts up without problems. Runs good for a while then it starts to produce white smoke from the exhaust, then it dies . If I try to start it again it just backfires. Sometimes it starts on 2 cyl and dies again. Plugs are black and really wet and smells like shit.

I have fuel pressure, injectors open up and I have a spark from the plugs?

What the f...k is wrong???

 

[Chris H]

I'd be doing a compresion test asap

 

[markeyturbo]

have you checked the wiring to the flux capacitor?

seriously tho, i had a similar prob, and a CTS fixed it, cured the cutting out and the rough idle

 

[Geronimo]

comp test done. CTS changed and signal sheckes at ECU end of wiring.

I had a friend (ex car mechanic) look at it today. He said fuel issue.

So I started (again) to look at everything that has with that to do. And there was one rhing I cound´t figure out:

The injectors open up in pairs, right?

There is 4 cables going to the connector at the fuelrail. 2 of them are ground. The other 2 goes to pin 20 and 21 at the ECU. Those 2 cables are cut and connected togheter at one point. Someone told me that they are supposed to be like that?
But then, how can they open up in pairs if both cables have contact with both pin 20 and 21? I my world that is impossible.

 

[Chris H]

no the injectors all open at once, its a batch/gang fire system so all 4 injectors fire at the same time.

Thats why the injectors all go into one wire as you found.

Also the switching is induced by switching to ground, the injectors are always live, the ecu earths them allowing them to fire.

Either you have an internal ecu issue (you said its fine on 3 ecus) that leaves the looms either shorting out flooding the engine via the injecotrs as you say you have changed everything else that controls the fueling.

I still say loom issue as you have replaced everything else more than once

 

[Geronimo]

no the injectors all open at once, its a batch/gang fire system so all 4 injectors fire at the same time.

Thats why the injectors all go into one wire as you found.

Also the switching is induced by switching to ground, the injectors are always live, the ecu earths them allowing them to fire.

Either you have an internal ecu issue (you said its fine on 3 ecus) that leaves the looms either shorting out flooding the engine via the injecotrs as you say you have changed everything else that controls the fueling.

I still say loom issue as you have replaced everything else more than once

I´m with you on that. Just have to find where.

 

[Geronimo]

Problem solved. It was a bad connection inside the connector between ECU and injector wiring. Easy to fix but hard to find.