more help rough idle, CEL, code 1222

[duckloads]

I need a bit more help, please, with my 1991 535i. The symptoms:

Rough idle all the time, worse when cold,

Barley runs shortly after hot restart or cold start followed by Check Engine Light-It runs fine when first started but then goes to crap for several minutes. During this time I can rapidly turn the engine off then back on and it clears right up.

After it clears up, it will scream all the way to readline in at least 3 gears.

I have replace badly worn spark plugs and dist cap and rotor, removed and checked vacuum check valve and hoses at brake booster (OK), cleaned idle control valve, and replaced other vacuum hoses. I can find NO vacuum leaks.

I checked the manifold vacuum and it's a steady 14 at idle. Punch the throttle and it goes to 24.

Thanks for any suggestions,

[duckloads]

bump

[JD525IA]

:/

I need a bit more help, please, with my 1991 535i. The symptoms:

Rough idle all the time, worse when cold,

Barley runs shortly after hot restart or cold start followed by Check Engine Light-It runs fine when first started but then goes to crap for several minutes. During this time I can rapidly turn the engine off then back on and it clears right up.

After it clears up, it will scream all the way to readline in at least 3 gears.

I have replace badly worn spark plugs and dist cap and rotor, removed and checked vacuum check valve and hoses at brake booster (OK), cleaned idle control valve, and replaced other vacuum hoses. I can find NO vacuum leaks.

I checked the manifold vacuum and it's a steady 14 at idle. Punch the throttle and it goes to 24.

Thanks for any suggestions,

[Kalevera]

What's meant by "badly worn spark plugs"? What color were they? White, black or ? Nice to know that there aren't any vacuum leaks, but have you checked the fuel pressure? Esp the hot start issue...points to the fuel pump and associated componentry.

[duckloads]

Thanks for the ideas. The spark plugs were a light brown color, but the center electrodes were worn rounded off and the gaps had increased to .036"-.041". Just long over due for replacement.

I have not checked the fuel pressure. I have done it on an e12 and other cars, but please tell me where to conect the gage on the 535i e34.

The only place I can find is the question mark shaped hoseleaving the regulator? Isn't that the return hose to the tank?

Thanks

[Javier]

Just under the intake manifold, there are two gas hoses coming up to the injector rail. They connect to metal tubing, one of them (Incoming) turn 90 degrees back to meet a short rubber hose and connect to the back side of the injector rail, the other, basically receives the returning hose. Then left hose, going up and to the rear side, is the incoming one, you will have to loose the rubber hose from the metal tubing, get a "T" to connect manometer, and a short rubber hose section to reconnect to metal tubing.

Javier

[duckloads]

Thanks for the fuel hose information. I'll pick up some hardware tonight so I can check my fule pressure.

[bahnstormer]

any updates?

[duckloads]

Thanks for asking. That was a long time ago. I noticed that the problem had gotten worse under wet/raining conditions. I took apart every electrical connection under the hood and cleaned the terminals with an emory board. I then filled the connectors with dielectric grease before reconecting them. I don't know which one it was, but I have never had anouther drivability problem with the car since then.

Good day,
Duck L