VW T4 Forum - VW T5 Forum banner
1 - 19 of 19 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
Hi,

1993 54,000 miles, 2.0 Petrol.

I wonder if anyone can please help?

Problem: When engine is warm it cuts out, sometimes for just a second, other times a change in throttle position or a gear change and power is back again, mostly happens going up hill (sometimes on flat) and normally on light throttle openings.

Tried so far, fuel filter, leads, cap and rotor, Plugs only done 4,000 miles but are three years old, cleaned and all look fine... new coil pack and module, temp sensor (4 wire one).

Have inspected throttle body and all ok, ran with fuel cap off in case a vacuum was being caused.

Thinking Crank Position Sensor? But wouldn't that just completly shut down when it fails? Or ECU? Really can't think of anything else?

Hoping someone can help, thanks in advance, Maf
 

·
Registered
Joined
·
1,668 Posts
Sometimes the ecu relay (no.30) can cause problems, they are about £15 from VW.
I had a similar problem with my 2.5 'velle and it was the engine speed sensor, they don't always show a fault or fail completely, they're about £60, took me ages, going thru the harness with a toothcomb, replacing ecu with a good 2nd hand one, replacing ht leads, hall sender unit...etc.
 

·
Registered
Joined
·
648 Posts
Hi,

1993 54,000 miles, 2.0 Petrol.

I wonder if anyone can please help?

Problem: When engine is warm it cuts out, sometimes for just a second, other times a change in throttle position or a gear change and power is back again, mostly happens going up hill (sometimes on flat) and normally on light throttle openings.
Classic 2l problem, should be relatively simple to fix, but can be caused by a number of different things.

temp sensor (4 wire one).
Right idea, but wrong sensor, I'm afraid! You need to replace the 2 pin sensor, which is the ECU temp sensor. The 4 pin one does the temp gauge on the instruments and the aux (electric) water pump. Definitely worth doing the 2 pin sensor as it might well be the root of the problem.

Also replace the small vacuum pipes that run from the left side of the inlet manifold to the air filter area and from the right side to the fuel pressure regulator and the ECU (on the inner wing). As these pipes age they crack and leak, causing problems.

Your Idle Stablisation Valve (ISV) might be causing problems. It's the silver cylindrical thing above the cam cover and should buzz when the ignition is turned on. If the above hasn't fixed things, try cleaning the ISV with carb cleaner or similar solvent.

There's an idle switch/throttle potentiometer on the back of the throttle body which can cause problems, although it's more likely to be one of the above.

There are other options, such as lambda sensor if you've got a cat, but try the above first.

Good luck and let us know how you get on.
 

·
Registered
Joined
·
32 Posts
had the same prolem with my 2lt petrol which also had not been used much for a period of time, after going through all the ussual bits it turn out to be the mapping sensor located in the ecu. i managed to find second hand ecu for £45. if it turns out to be this pm me & i'll tell you where i got mine from. good luck with the fix as i realy like the way my petrol van drives.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #5 ·
Hi,

Thanks, will try 2 pin sensor first as it's defo temp related, when fully warm it runs fine so its defo getting confused with the warm up period, common on a lot of vehicles, my Cherokee 4.0 had the same fault.

Will let you know, cheers Maf
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #6 ·
Classic 2l problem, should be relatively simple to fix, but can be caused by a number of different things.



Right idea, but wrong sensor, I'm afraid! You need to replace the 2 pin sensor, which is the ECU temp sensor. The 4 pin one does the temp gauge on the instruments and the aux (electric) water pump. Definitely worth doing the 2 pin sensor as it might well be the root of the problem.

Also replace the small vacuum pipes that run from the left side of the inlet manifold to the air filter area and from the right side to the fuel pressure regulator and the ECU (on the inner wing). As these pipes age they crack and leak, causing problems.

Your Idle Stablisation Valve (ISV) might be causing problems. It's the silver cylindrical thing above the cam cover and should buzz when the ignition is turned on. If the above hasn't fixed things, try cleaning the ISV with carb cleaner or similar solvent.

There's an idle switch/throttle potentiometer on the back of the throttle body which can cause problems, although it's more likely to be one of the above.

There are other options, such as lambda sensor if you've got a cat, but try the above first.

Good luck and let us know how you get on.
Tried the 2 pin sensor, no joy, truck really a nightmare on hills, will look at other stuff next... don't use it a great deal and fed up of replacing parts, can it be hooked up to a computer to find the problem?

Thanks again, Maf
 

·
Registered
Joined
·
1,369 Posts
l also have a 2ltr petrol 1995 with 87,000 on the clock.

l had poor idle problem in the past, seemed to go when l changed similar parts as discussed, trial and error.

it seems to have returned, idle problem that makes the engine run like a kangaroo, not always, but enought to drive you mad.

vacum pipes are worth doing, only a few quid and 20min job. have you checked exhaust/manefold/lambda? and manuel discusses these parts in relation to idle/stalling?

hope you resolve problem, keep fellow petrol members posted of new ways to sort this problem out. A:
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #8 ·
Thanks again for advice,


The thing that puzzles me is this, from cold, perfect, when fully warm (sitting in traffic the needle is on the half way mark) it's pretty much fine.... it's when the temp is between the cold and half way point that all the problems start... so I since I've changed the temp sender I think it must be what the ECU is doing with the info that is causing the problem?

Cheers Maf
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #10 ·
Try the fuel pump relay, not sure if it's the one mentioned earlier....2 minutes to fit and costs £20 ish

Caused me some really rough running problems for a while.
Tried, sadly didn't cure the problem, I've cleaning the ISV valve.

Managed to get the fuel pump relay for less than £10 at GSF, hope that helps?

So really stuck now... the part number on the ECU is 044 906 022E are others inter changable?

Thanks again for everyones input.... Maf
 

·
Registered
Joined
·
648 Posts
This is a puzzling one. As you say, the fact that it runs fine when warm points to temp sensor, but changing it has made no difference.

Have you tried anything with the throttle position sensor (TPS)? It's above the manifolds so probably warms up as the engine gets hot, which might make for an intermittent fault. I think the van will run with it unplugged (not done it myself, but seem to remember someone saying they had). If it will run with the TPS unplugged, it would be interesting to see if it made any difference.

Otherwise, I wonder if it's something funny like a damaged cable which is being effected by changes in temperature. Might be worth a careful look round.

Good luck.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #12 ·
Have managed to find a ECU for cheap as chips, although not the same part number, same engine type, fingers crossed.... will let you all know what happens when I plumb it in.

Cheers Maf
 

·
Registered
Joined
·
2 Posts
Have had cutout/stall problems on my 92 2.0l (184k and still going strong)...

  • Stall (at junctions etc) - leaking vacuum pipes - £2.50 ebay/15 mins to change.
  • Running Cutout (intermitant when warm) - faulty TPS - £30 ebay/10 mins to change.
Mark...
 

·
Registered
Joined
·
4,254 Posts
Interesting thread.

My 2.0ltr runs terrible/cuts out when cold. It's in the workshop at mo so hoping they get to the bottom of it- will post on here when I get her back, ya never know, it may help you.
 

·
Registered
Joined
·
1 Posts
I have had my 1995 2.0 litre T4 for 5 years and it had been driving me crackers. All of the above problems and my local garage releived me of nearly £600( idle control, TPS, Lamda and various other sensors )and still could not find the problem. After joining the T4 forum I read that Relay 30 could be the cause. I have now changed the relay and all the problems have gone.
 

·
Registered
Joined
·
5 Posts
Had exactly the same problem.
I figured the problem had to be in the electrics because when the engine failed it would sometimes load up with fuel and backfire when the electrics came back to life.
I changed the ignition transformer and that didn't fix it, I pulled the distributor apart and cleaned and checked everything, I checked the ECU the best I could and figured that was OK.
The only thing left was the Hall Effect sensor in the distributor and that's what it was.
Engine runs fine now.
 
1 - 19 of 19 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top