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[Stige]

I have a weird problem.

First things first, car came to me as "died while driving" and didn't start.
Replaced stuff like plugs, coil, crank sensor no luck. Finally I found out that the crank gear had spun so timing was completely off.
Now with that sorted out it actually starts and runs.. well sort off.

Everything plugged in correctly, it only runs with pedal to the floor or close to it and smells god awful and gives me a headache, just like it was running REALLY rich.
If I then go and create a vacuum leak, it actually idles now, which again makes me think it's getting flooded with fuel.
When I take the Idle Control Valve hose off the pipe going to intake manifold, it idles at 900-1000rpm and sort of drives if I keep the pedal down enough.

I tried to find a vacuum leak at first with brake cleaner but there aren't any I think. Also if I take a vacuum hose off and spray near it, it actually dies instead of revving up like it usually does with a carb cleaner when you have a vacuum leak.

But why? What causes this? I really got no ideas.
Engine light is not on either so can't even get a clue from that.

[Doctor Gollum]

Will it start/run from cold?

If no, will it start with some throttle?

If yes, suspect ICV jammed shut.

[Stige]

Will it start/run from cold?

If no, will it start with some throttle?

If yes, suspect ICV jammed shut.

I'm not sure how ICV is supposed to operate but it rotates when I give it juice and the connector to it also has voltage so I think it works fine.
Checked with a tester today and temp sensor seems fine, both Lambda sensors were basically stuck at 0.8V, sometimes showing 0.9V but never below. Suspect they are just some cheap copies and ordered new genuine ones so will find out tomorrow if it helps.

[Andy H]

My understanding is that the lambda sensors read 0.8v when rich or 0.2v lean so yours are behaving as expected.

Have you got a way of reading the long term fuel trims?

Have you tried running the engine with the MAF disconnected?

[Stige]

My understanding is that the lambda sensors read 0.8v when rich or 0.2v lean so yours are behaving as expected.

Have you got a way of reading the long term fuel trims?

Have you tried running the engine with the MAF disconnected?

If I disconnect MAF it loses any sort of idle completely but works if I use the throttle.
MAF readings were showing 20 (idle) to 140 (revving).

I don't think I can get that detailed access to stuff like those fuel trim infos.

Also at the shop I went for the readings, they said that 0.8V is lean apparently. But I don't know which way is actually correct.
But either way the fact that neither of them really moved at all would suggest there is something wrong with them? I'm taking them off tomorrow to see what brand they are and to try new ones.

[Stige]

Now that I think about it, it should run when cold right? If the problem was the O2 Sensors?
Apparently they are not used when car is cold, only when warmed up?

[Marks DTM Calib]

What is the throttle position reported to be via live values?

[Stige]

What is the throttle position reported to be via live values?

Can I measure this with multimeter? Dont wanna take another trip to the shop to read them again.

[Marks DTM Calib]

Possibly, has per chance the plenum or the throttle pot been swapped? (looking to rule one possibility out)

[Stige]

Problem solved I think, well almost, but atleast I know the cause now.

Swapped both O2 sensors today, still didn't idle, unplugged MAF again = voila car actually runs and works now!
It didn't make a difference yesterday if I unplugged the MAF sensor.

So off to get a new MAF tomorrow and it should work like a charm now.

But what are the odds that O2 sensor/s and the MAF are all broken...
Well I bought the car as "doesn't run, died while driving" but didn't expect this much.

[Stige]

Problem 100% solved now.

MAF housing was upside down...
I realized this after I took some photos of the housing for the part numbers on it so I could order a new one.

And I never took the housing off from the "middle part" of the intake thingy so it was always like that...

Well I'm glad this was finally solved!