De Lorean EuroTec

Hopefully you guys can help. Following stripping down the engine to reveal the VOD, and putting every back together after what turned into a far bigger job than I thought it would be (loads of "while in there" tasks") the engine is running all over the place, not to mention potentially overheating!

I stripped of everything to get to the VOD, only to find a coolant leak, and a water pump which was well past its best. Therefore I decided to do a few extra jobs while in there. They included:

paint the VOD after cleaning.
New water pump.
New cap, rotor and HT leads
New silicone hoses and Silicone Vacuum hoses.
Two new sensors in the Y pipe, just not the thermotime switch (none available).
New gaskets and o rings throughout.
Generally cleaned everything and gave quite a few parts a coat of high temperature paint.
New stainless bolts for everything.
Adjusted the valve clearances as well.

You'd think after all that turning the key should have resulted in a purring engine, but no. Instead after quite a few cranks of the engine it started, but the idle shot up to 2000 rpm and stayed there! The engine seemed to get VERY HOT very quickly, especially the exhaust. The exhaust seemed louder as well, and there was a smell of unburnt fuel.

In a bit of a panic move I decided to mess with the idle screw setting, which did bring the rpm down a little, but not to where it should be or was before I started the job. After that I did the worst thing possible and moved the screw back and forth without really taking note. Yeah I know, bad idea, stupid, you name it. Now it's probably way off.

Attaching a dwell meter as I did last year to set it up just produced a very odd reading. The needle just plants itself right to the right hand side and doesn't move at all. I'm not sure the frequency valve is functioning as it should as well. I can't seem to hear it at all except for one time when it seemed to be running all the time. I've checked the ground point for this on the manifold and that checks out.

I can't see where there would be any vacuum leaks. The injectors went back in ok, and everything else checks out. I'm pretty sure I put all the vac pipes correctly.

Also, even after burping the radiator and bleeding the water pump at the top the radiator stays fairly cold, while the engine seems very hot.

The car was running perfectly before I started and had never had an overheating problem. The rpm was spot on, as was everything else other than the major coolant leak in the VOD.

I really need some ideas. I'm moving out of this house on the 28th, and need the car to run so it can move as well! At this rate it'll become a permanent fixture.

Any ideas?

Are you sure you removed *all* the paper towels from the air intake holes?

RobvdVeer wrote:Are you sure you removed *all* the paper towels from the air intake holes?

Who would do a silly thing like that! lol.

Chuff, where would I start?

Do you have a cat bypass pipe? If you have do the following:

Disconnect and plug the vac advance pipe.
Disconnect and plug the vac pipes to the control pressure regulator.
Disconnect the oxygen sensor electrical connection at the bulkhead blade connector at the fuel computer/body tub bulk head.
Ensure that the little "hammer" presses on the throttle switch when the throttle is closed.
Double check that the fuel pipes from the control pressure regulator and the frequency valve go to the correct banjo bolt on the fuel distributor.
ensure that the o ring at the idle speed control valve pipe to venturi manifold is intact and the pipe fits fine.
Double check the spark plug ht leads are correct to the appropriate cylinder.

Only if the above had been done, adjust the fuel adjustment with the hex key to adjust to the smoothest setting (ideally use a gas analyser to set to 1.5% co)
re-check that the timing is back to 13deg btdc.

This should result in a drivable car. Without looking at the car and doing tests it will be hard to diagnose. Good luck

Also to add, at the White multi plug at the idle ecu, check the resistance of the thermistor. Approx 10k-12k ohms when the engine is warm. A higher reading when the engine is cold.

EDIT: 10k-12k when the engine is between 15 deg c - 20 deg c

Cheers Nick. I might pull some of the parts and check everything again. Something must be put in wrong, loose or not fixed correctly. Probably something small. I'm thinking the pipe of agony is a possibility.

As for the paper towel, pretty sure that was all out.

Or you had an air leak and someone adjusted your fuelling to compensate

Bit of an update. Stripped everything down to the VOD again. Found that one of the seals on the W pipe had ripped, so that wouldn't help. Also a couple of the injectors didn't seem to be seated correctly. I inserted them after the air intake, which makes it harder to secure them. Checked the thermostat which seemed to take too long to open in a pan of boiling water, so that was replaced with a new one which also included a small hole in the top section (as per Nick's recommendation).

All back together and the coolant problem has been sorted, but the engine still ran like a bag of nails, even chucking out loads of soot! Ran both rough and very warm as well.

Looking through all the new parts I added I noticed that the bosch spark plugs I added had a 0.8 gap, where as the manual asks for 0.6. So, pulled them out and re-gapped them to 0.6. They also got a clean as they were pretty sooted up. Then one spark plug on cylinder 4 (the bugger to get to with the idle motor and CSV in place) refused to go back in and kept getting cross threaded. So in the end ended up taking everything back out and sorting them.

With everything back in started the car back up. Started right on the money, and ran smooth, if again higher than I would like at 1200 rpm. Then disaster. One of the coolant pipes, the left one going into the block, had a clip I needed to slacken off to get the manifold out. I'd forgotten to tighten it back up so it proceeded to spray coolant into the VOD again!

Stripping it back down again (I'm getting good at that one) I cleaned the VOD again, put it all back together again, only to have TWO banjo bolts break right off when I tightened them up (not too tight I might add).

The car seems not to want to move. I have to be out of this house on Tuesday next week, so more bolts ordered for overnight delivery.

I'm starting to fall out of love for the machine now. I swear it's cursed, or just bloody stubborn!

oh, and the thermister had odd readings. With it out of the car it had a resistance of about 12K at room temp, dropping to 3-4K in hot (80 plus) water. Very odd.

Like every relation, you get to live with the good and the bad bits. Having done this you'll only love her more.