I got off the freeway to my destination and it was missing really bad. running on 3 cylinders. Get it to the shop to look at it. Pinpointed a bad wire.

New plugs and wires maybe a month later running rough. Inspect, see spark at plug boot. Figured out the wire has a manufacture defect, internal the wire doesn't goes as deep as the others and not making a good connection.


Question I'm using the plug wires with the metal boots at the end. But when I went to the parts store wires without the metal boot are called for stock???


Are the metal wires or the regular wires stock on 740 and 940 turbos?

 

Use Bougicord wires and NGK Copper plugs. These cars are sensitive to aftermarket variations and may run poorly with them. "Metal boots" wires are a no-no.

 

I swore we always used to use the plugs with the metal boots at the shop I worked for. There's so many variations and different part numbers for these cars.... Where I bought the wires they warrantied the parts already. Had to order another set of wires. I'll use Bougicord next tune up.


Only #3 runs bad. I pulled out the scope to check coil primary, injectors, 02 responses, etc. Then stopped gain composer and did a simple balance test. #3 not contributing, seen sparks boot. KISS. If I had a secondary adapter I would easily seen it on my scope.

 

I got Kingsbourne wires and they work great. They have a metal boot over the rubber boot and give me no problems. They did once fail because I had an exhaust leak. It melted everything inside the metal jacket and allowed arcing. I would make sure that you do not have an exhaust leak at the manifold gaskets. I replaced the gaskets and the boot ends (easy from Kingsbourne) and have driven the car across the US with no problems. That's what I would check into on your car.

 

Damn I have just developed an exhaust leak at the manifold.

I have to do that and fix some leaks.

Oh, yeah so I got a new set of wires, metal boots, and a single plug: it runs great.

 

This. I have an exhaust manifold gasket leak that needs to get fixed asap.

Bougicord wires will not melt? If there's no exhaust leak of course?


Anygood write up on turbo removal or exhaust manifold. I could figure it out, but it's nice to see before starting to job.

 

I use Bougicords because they are OEM, all rubber, always work fine. Sure, if they get hot enough they melt; exhaust leaks put out a lot of heat.

I just did exhaust manifold gaskets job on my '89 760t to cure exhaust leak in #1. Worst thing to watch out for: studs/nuts breaking off in the head... How do you cure that? Also there is one nut, a bitch to get at to remove, believe the #2 cyl. I bend the plug shield to get to it. The turbo oil return pipe has to be undone to move the manifold a little to clear the studs in order to put the new gaskets in. On a Mitsubishi turbo, not so bad; on a Garrett, good luck! The one I did was a Garrett and it was a pain but I got it done eventually.

 

Yeah, I'm pretty sure I have a garrett. I looked it up, book time is 3 hours. I'm debating going in on my day off and having all day or doing it after work which would give me 4 hours.

 

An 88 should be a Mitsubishi, I think, the bigger one. With an exhaust leak no spark plug wire will hold up. Shoot all the nuts with PBlaster the night before. Mine came off super easy that way. Don't forget the other nuts that are easily forgotten: on the outlet of the exhaust housing, the one on the bottom of the manifold that goes to a bracket to the block. I found the oil line to the block a real pain to get loose. I've taken the oil cooler boom loose to do that. It's a 32mm nut. It's a shame that I know that off the top of my head.

 

exhaust manifold gaskets on a turbo is no joke. spent almost 4 hours.

Luckly I didn't break or strip any bolts,. My drain tube was leaking so I was able to fix that at the same time.

I simply disconnected the exhaust from the bell housing, removed the drain tube, disconnected the turbo from the block bracket, and disconnected the turbo oil feed at the turbo and simply pulled the whole assembly back. I wasn't able to clean both surfaces as well as I would have liked to, but the gaskets came off pretty much in tact it it wasn't so bad.

Long story short it was a pain the butt. No more exhuast leaks and hopefully no more burnt plug wires.