Problem with my '89 Turbo

[tro-se]

Hi all,

I have a problem with my '89 Turbo Esprit. It misses badly on part or full throttle when it is off boost. Once the revs rise and the boost comes in it picks up and goes fine.

So far I have done the following;

1. Replaced spark plugs
2. Replaced dizzy cap
3. Replaced the plug leads
4. Checked the ignition timing at idle

Any ideas guys? Its got me scratching my head.

Many thanks in advance.

Dan

[B16 RFF]

Coil?

[feffman]

Tro-SE:

Fuel and air filter??

Feff

[Dr.Hess]

Is this a carbed turbo? Because all the other 89's don't have dizzy caps. I'm not sure about the carbed turbo. If it is a carbed turbo, then I would say you almost certainly have a carb issue with one of the idle or slow speed circuits clogged up.

Dr.Hess

[tro-se]

Yeah its a carb turbo. I'll have a look into carb problems. Thing is, three of the plugs look very black (rich - ie. not firing) after a bit of a run.

Confused!!!

Ian

>> Edited by tro-se on Thursday 1st December 19:22

[Dr.Hess]

Well, that plug that isn't the same as the others would be a good place to start. Pull that carb apart and have a look, especially on that barrel. Pull all the jets out, soak in cleaner, blow through with air, etc. Has the car sat for a while?

Dr.Hess

[tro-se]

Yeah its sat for about 9 months. So you don't think its ignition timing related then?

Ian

[Dr.Hess]

No, I would say it is almost certainly gas gunked up jets, most likely the one that is not black. I got through 5 years of undergraduate school and 4 years of medical school like this: "One of these things is not like the other, three of these things are kinda the same, but one of these things is not like the other, now it's time to play our game..." From Sesame Street. You have 3 black plugs and one not black plug.

There is no easy way to un-gunk them. You have to take them out of the carb, soak them in some cleaner, blow them out, inspect and maybe run a wire or small drill bit through in extreme cases. They always say don't do that, but I have to un-gunk the carbs on my bikes after the winter, and that is what I always wind up doing. Using a fuel additive like Sta-Bil helps a lot but doesn't guarantee not having to go through it. Given your miss, I would think it is not the main jet, which is in play with boost and at higher RPM.

Dr.Hess

[B16 RFF]

I would say the problem is 3 cylinders are running much too rich, which explains why the car runs OK at full throttle/boost. Maybe the fuel pressure regulator is faulty. This is the device that maintains fuel pressure at a fixed value above inlet manifold pressure. If it has stuck at the full boost value, it could be flooding the carbs at lower inlet pressures. I very much doubt that you have blocked jets if the car has been standing for a relatively short time.

Blow through the jets with air if you will, but do not poke anything metallic through them under any circumstances. It's unlikely you will need to anyway. I have stored my Excel for much longer than that, and the carbs and fuel have been fine.

Paul

>> Edited by B16 RFF on Thursday 1st December 22:28