[Mk2] [Turbo] Ongoing technical issue = losing love for my turbo! Help!

[Kumakun]

I'm feeling cursed. I've had three turbos in the last fifteen years and all of them have given me hell!

I have a 1992 Rev2 Turbo (pic in my profile garage) that for awhile now hits 4k revs in 3rd and 4th under hard acceleration and just sits there and struggles. The car isn't really modified just a manual boost controller set to 12psi, after market exhaust and induction kit and that's about it to my knowledge.
It's probably something trivial but I need to get to the bottom of it because it takes all enjoyment out of using it.

So far I have replaced all ignition parts including leads, coil pack and igniter module.
Luke at Pacific suggested switching the ECU but we haven't had chance to try that yet.
The turbo does spool up well but I'd say that the delivery isn't as smooth as it should be. More like a slight hesitation before getting it in a lump at which point she'll hit a wall. Strangely it doesn't seem to happen in 5th.

Any suggestions greatly appreciated.
I am considering a rev3t transplant (see my ad in the wanted section) but if that goes ahead then this engine will end up in my MK1 so I still need to figure out the problem.

Looking forward to hearing from you!

[bobhatton]

I'm feeling cursed. I've had three turbos in the last fifteen years and all of them have given me hell!

I have a 1992 Rev2 Turbo (pic in my profile garage) that for awhile now hits 4k revs in 3rd and 4th under hard acceleration and just sits there and struggles. The car isn't really modified just a manual boost controller set to 12psi, after market exhaust and induction kit and that's about it to my knowledge.
It's probably something trivial but I need to get to the bottom of it because it takes all enjoyment out of using it.

So far I have replaced all ignition parts including leads, coil pack and igniter module.
Luke at Pacific suggested switching the ECU but we haven't had chance to try that yet.
The turbo does spool up well but I'd say that the delivery isn't as smooth as it should be. More like a slight hesitation before getting it in a lump at which point she'll hit a wall. Strangely it doesn't seem to happen in 5th.

Any suggestions greatly appreciated.
I am considering a rev3t transplant (see my ad in the wanted section) but if that goes ahead then this engine will end up in my MK1 so I still need to figure out the problem.

Looking forward to hearing from you!

Have you checked for fault codes?
After checking reset the ecu.
Remove the boost controller and put the stock control back on.
What fuel do you use?
What is your timing set to?

[Kumakun]

Had the fault codes checked and cleared at Pacific a couple of times.

I have thought about removing manual boost controller... Might do that next.
Always use v power.
Not sure about timing.

[2mad]

slight hesitation before getting it in a lump at which point she'll hit a wall. Strangely it doesn't seem to happen in 5th.

Are you hitting fuel cut mate .. remove the vac hose from the map-sensor and cap it off to do a test to rule it out .

[craig]

Had the fault codes checked and cleared at Pacific a couple of times.

I have thought about removing manual boost controller... Might do that next.
Always use v power.
Not sure about timing.

So what does Luke think it is?

[bobhatton]

Had the fault codes checked and cleared at Pacific a couple of times.

I have thought about removing manual boost controller... Might do that next.
Always use v power.
Not sure about timing.

And what were the codes?

[Kumakun]

No, it doesn't feel like fuel cut. I've experienced that before.

Next time I see Luke I'll get the codes checked again. He usually knows them in his head.
Luke was surprised it wasn't the igniter or coil pack. His next thought was the ECU could be faulty.

[Kumakun]

The only significant fault code I had was for the air flow meter when the car was running very grumpy. Switched for another (possibly recon because it looked like new) and solved it.
The 4k revs issue was sometime after that. I was hoping that it was a common issue that others have experienced...

[mr2magic]

Check static timing..could be you've jumped a tooth or two. Other than that..maybe ecu but the two cases I had were always extremely lumpy idle and misfiring etc.

[Peter Gidden]

Check static timing..could be you've jumped a tooth or two. .

Agreed.

Cheaper and easier to use a methodical approach instead of guessing. First check mechanical side of things, so pull back top belt cover and check cam timing.

Then check ignition timing.

Clear codes and take out for drive til fault occurs. Check codes. And write them down.

[Kumakun]

Well thanks for your suggestions. I'll be looking into this ASAP.
And if anyone can help out with a rev3+ engine then please pm me.

[Kumakun]

Thanks all.
Somehow the timing was suddenly way off! I didn't touch anything, I swear!!
But it's all fixed now.

[Peter Gidden]

Thanks all.
Somehow the timing was suddenly way off! I didn't touch anything, I swear!!
But it's all fixed now.

Cam timing or ignition timing?

[Kumakun]

Ignition

[Peter Gidden]

Ignition

Well there's only 3 reasons:

1) it was already out
2) inlet cam has slipped a tooth
3) timing troll changed it one night without you knowing

Did you check the cam timing like i suggested?

[Kumakun]

Well I just left it in Luke's hands (Pacific).
When I bought the car it was running very nice. It was my 3rd turbo and it was how I expected it to be. Soon after I had that issue with the air flow meter. It was changed and the car was better but still off.
I'm very happy with how it's running now but the cambelt should be changed in a week or two anyway as I'm suspecting it hasn't been done for a very long time.

[MartinF]

Well there's only 3 reasons:

1) it was already out
2) inlet cam has slipped a tooth
3) timing troll changed it one night without you knowing

Did you check the cam timing like i suggested?

Or somebody didn't tighten the distributor properly after adjusting last time.