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Mon Jul 11, 2005 8:09 pm

I have a 93 MV 5 Speed that does not want to idle or rev above 3,000
RPM's.

I have tried the following:
I hooked up the diagnostic tester which showed no codes.
I replaced both coolant temp sensors, and the throttle pos sensor...no
changes.
I replaced the vaccum sensor on the ECU board... no changes.
I relaced the vaccum lines.
I tested the Intake air temp sensor which seems to be good.

The van seems to be getting fuel and spark just fine, and I made sure nothing is restricting the exhaust or intake.

I contemplated changing the hall sensor and the coil, but it seems
like when they go, they disable the van. My van always runs, so this
doesn't seem right.

I had an older GTI that did the same thing and ended up needing a
knock sensor control unit. I am unaware of this control unit on the
eurovan.

Should I try a whole new ECU? Does anone know of a good source for a
used one to try?
Thanks for your time,
Cheers,
Kris in St Louis

Tue Jul 12, 2005 7:12 am

Before you spend some real money on this thing, test the fuel pressure and pump volume to see if it is within the spec. That is cheap.

Sometimes the injector spary patterns are not that nice little cone that we like to see. Do the Bentley test on them and perhaps send them off for cleaning and calibrating for cheap money (like $15 each). Do them all since it is still cheaper than replacing just one of them. Also cheap to do.

I assume the Monday through Friday maintenance suff (plugs, hoses, timing) has been done to you are sure there are no vcuum leaks and poor electrical connections.

Tue Jul 12, 2005 11:42 am

Thanks for the advice. I'll do some fuel system work and let you know how it turns out.

Why does everyone hate Eurovans?

Kris

Tue Jul 12, 2005 11:47 am

I don't hate them, just never had one or even ridden in one by the way.

Hell I have never ridden in a Vanagon or even listened to a Maria Carey song for that matter.

I really don't get out much. :-S

Thu Jul 14, 2005 9:05 pm

No luck with the fuel system check, I have adequate fuel pressure.
I also have what appears to be good spark to all 5.

Next up compression check, and I'm buying a used ECU for the hell of it, maybe it'll be the answer to all of my problems.

Kris

Fri Jul 15, 2005 7:22 pm

So when you do the fuel system check as per your bentley you are able to rule out 1) vacuum leaks 2) adequte fuel pressure at start up time 3) adequate fuel pressure at 3000 rpms and 4) it passes the volume test X volume in Y seconds.

I would then pull the injectors out and see if they are all munged up and don't spray well.

Run a compression test (engine warm) and see what you get. Do the "oil squirt" and see if that changes things. Do a leak down test if the compression test does not tell you what you want ot know.

Fuel filter is good? If you chang it out, cut the old one open and see if there is anything wierd in it.

O2 sensor test out OK? Idle stabilizer test out as per the Bentley? How about the cat converter if you have one?

ECUs so seldom go bad, everything else is suspect first.

Sun Aug 07, 2005 9:14 am

I'm still battling this thing. Any advice would be appreciated.
I bought it with the problems described, and the previous owner said it just started doing this, no gradual change.

-I've totally eliminated the possibility of the exhaust or intake being clogged.
-I've tried a new (junk yard) ECU.
-I've tried a new sensors (Intake Air Temp, both coolant temp, Throttle Position).
-I've run the VAG diagnostic tools (no codes or unusual readings).
-I've replaced vaccum lines.
-I ran the fuel pressure test.
-I have new injectors on the way.

This van is clean under the hood, I 've visually checked the harness and it looks uninterrupted (not pinched or stressed). The grounds are not ugly.

I've found that the header is cracked (I thought it just needed a gasket). I know the cracked header probably doesn't have much to do with my problem, but it's easier to hear without exhaust noise under the hood.
Thanks,
Kris

Sun Aug 07, 2005 9:46 am

Is this something that just suddenly happened? How is the base timing? Does the spark advance? Any warning lights coming on? Usually if the vehicle starts and runs at all, the ECU is good. Start with the basics.

Mon Aug 08, 2005 8:27 pm

GOT IT!!!!
The idler pulley on the timing belt froze up and the timing belt jumped a tooth. Lucky for me it didn't jump more and bend valves.
So, hundreds of dollars later, it takes 100 dollars worth of parts to fix it.

I can't wait to get this thing on the road!!!!
Thanks for all of the advice.
Cheers,
Kris