240 fuel/speedo?

[jkior]

Got a frustrating no-start problem with my '88 245DL. Starter moter turns, have spark, have battery, have fuel, fuel pumps work, blah blah. I believe the problem is that the injectors don't fire. I've done the Bentley ecu/icu tests, and many other things, can't find a thing.

Just yesterday I noticed that when I turned the key from the II to the III position, the speedometer jumps quickly to ~70, with a kind of jerk at 30 and 50, then drops immediately. What? I pulled the ignition switch, and it does everything that the manual describes. I don't know if the problems are related, but they might be.

BTW, the timing belt is fine, replaced the fuses and panel, replaced air filter, replaced fuel filter (fuel does flow to the rail, just not through the injectors). The engine did turn over once at first turn for a while if left for a while between starts, which would indicate to me a little leakage, maybe? The last repair was replacing the brake lines and replacing the fluid, and the car ran fine immediately afterword, but wouldn't start two days later.

I'm totally out of ideas at this point, so thanks for any help you might be able to give.

mike

 

[Three Fat Tigers]

With the fuel pump relay (aka LH injection relay) bypassed (make up a Y with three male blade push on connectors inserted into terminals #30 & #87/1 & #87/2 of the relay socket) make sure both fuel pumps can be heard, then verify there is 12V+ present at one of the terminals of any fuel injector connector. If you are getting power there, try cranking, and if the injectors dont click as you crank the engine (you should be able to feel/hear this), your ECU or wiring harness has a fault and may need to be replaced. Make sure the battery cable ground to the engine is in good order, make sure the ground points at the bolts that hold on the fuel rail are in good order.

Have no idea about the speedo jump, never heard of that type problem before.

 

[jkior]

Yeah, I tried jumping at the relay, and both pumps work. (Tested seperately) I also get fuel pressure at the fuel rail.

There seems to be 12V at the injectors. (Both terminals?) The injectors don't seem to click when the engine is cranked, and they definately don't fire - I had the whole rail off to test this. (replaced the o-rings while I was there)

Grounds seem to be good - no undue resistance between ground leads and the battery ground terminal, but - where's the engine ground? Ground bolts are good.

Any tips on a wiring harness? FCP prices them at $440, which is really starting to exceed the value of the car. Does anyone have any hints on commonly damaged areas on the '88 harness?

BTW, LH2.2