$500 in parts- now have stumbling issue

[ClassicScot]

any news on this i really want to know how this turned out.. hope you got it figured out.

[bimmerboy12]

UPDATE: I pulled the valve cover last night and verified the valve tappet clearance and everything still looked good. I also put RTV on both sides of the valve cover gasket as it looked like there was still a little oil seeping through even though it was brand new.
I then did a valve soak with seafoam- let it drink the whole 16 oz. can at idle through a T in the fuel regulator vacuum line, had to pinch the hose to regulate or it will die. Added half can to the crankcase and the other half in fuel.....

WOW!!! MY CAR IS SOOOO MUCH FASTER!! It absolutely screams. It was like driving a different car.

However, the idle problem is unchanged. bummer.
Next is a coolant system bleed this weekend.

[bimmerboy12]

The Seafoam treatment might help... it certainly won't hurt.

Is Seafoam essentially equivalent to Ventil Sauber?

Clasicscot, my next plan of action is to pull the valve cover, re-measure my valve adjustment, and ensure everything is OK with the valve cover gasket. I will also re-bleed the coolant system just to make sure.

[ClassicScot]

crank sensor? spacing might cause a stumble could be exposed wiriing happend to me but this also cause temporary paralysis of my car! Maybe just adjust the throttle, could just be silly and needs to be adjusted slightly. You mentioned valve cover gasket, did you make sure the seal was tight no burrs or gouges? Some of these may sound stupid but it might just be a fucked up stupd thing.

GL
Andy

[bimmerboy12]

Redo the test...can't hurt. Make sure engine is hot.
Throw a tablespoon of oil in those cylinders with low compression if you get low numbers again. If worn rings, you should see the number go up with oil in the chamber.

OK, I am embarrassed to admit this, but I did the test wrong the first time... I just got this new compression gauge, and there is a screw-on connector at the end of the hose. So after I unscrewed the hose from cylinder 1, I unknowingly left the connector in cylinder 1 and screwed the hose right into each following cylinder, giving erroneous readings. SO... here are the NEW and IMPROVED readings:

1 - 145
2 - 145
3 - 150
4 - 165
5 - 150
6 - 150

Cylinder 4 may have some carbon build-up.

REGARDLESS, I think I am getting off-track from the root cause. Remember, this problem started when these new parts were put in.

ALSO- I re-tested the resistance of the CPS with my dad's ohm meter, and his measured it at 540 ohms, which is right on. My brand new ohm meter is faulty.

ANY OTHER IDEAS??? KEEP THE IDEAS COMING I WILL TRY ANYTHING!!!!

[bmwpower]

Redo the test...can't hurt. Make sure engine is hot.
Throw a tablespoon of oil in those cylinders with low compression if you get low numbers again. If worn rings, you should see the number go up with oil in the chamber.

[Hallen]

Yeah, those numbers are way low. Factory new is something like 150, but on older engines it isn't uncommon to see it up around 170. So either you have a problem there, or you didn't do the test right.

The Seafoam treatment might help... it certainly won't hurt. But you have something else going on there that, in my opinion, isn't right.

[Keanan]

another update: I did a compression test and got the following:
1 - 144
2 - 120
3 - 125
4 - 120
5 - 110
6 - 115

Not that great, but not bad and pretty consistant.

While the motor was running, I sprayed carb cleaner on all the injectors and didn't note any change in the idle.

On another note- it idled WAY better today... I don't know why, but it was 66 degrees today maybe that had something to do with it??

Have you been keeping records of what you have been testing and the results of those tests?
Your compression numbers are not really consistent. #1 has 144 psi and #5 has 110 psi? Redo your compression test just to make sure your numbers are accurate. I think they are supposed to be closer to 150, but check your Bentley for the exact spec.
In order to keep your sanity and and prevent ulcers I say you take it somewhere. Find a shop that has certified technicians that know a lot about older BMW's. Give them a list of what you have tested and the results of those tests. Then pay them for one hour of diagnosis. If your compression numbers are still low then have the shop do a leak down test.
In the end you should have to pay the shop for 1 hour of diagnosis and maybe 1 hour for leak down. If they don't find it then you can consider pay for another hour of diagnosis.

If you don't want to pay someone then I understand. It is usually easier to spend 7 months trying to figure out a problem than paying a shop for 2 or 3 hours of work.

[bimmerboy12]

another update: I did a compression test and got the following:
1 - 144
2 - 120
3 - 125
4 - 120
5 - 110
6 - 115

Not that great, but not bad and pretty consistant.

While the motor was running, I sprayed carb cleaner on all the injectors and didn't note any change in the idle.

On another note- it idled WAY better today... I don't know why, but it was 66 degrees today maybe that had something to do with it??

[gtarwiz]

ok, this may sound kind of out there, because I to am having some idle problems, but different from yours, but another place to maybe check for a vacuum leak if you haven't already is the injectors themselves. From what I have read if the seals go bad on the injectors then it can give a really crappy idle. I dunno, just a thought.

-Griffin

[bimmerboy12]

have you done a compression test? long shot but it may surprise you. my eta had the same problem needed rings no other symptoms but bad idle after new timing components were installed. also did you try swapping ecus with another car that idles well. just a thought

I will run a compression test, good idea. I have no access to any ECU's but will keep an eye out for a cheap one.


Any input on the vacuum readings I got?

[tallscott]

have you done a compression test? long shot but it may surprise you. my eta had the same problem needed rings no other symptoms but bad idle after new timing components were installed. also did you try swapping ecus with another car that idles well. just a thought

[bimmerboy12]

no input guys? Im gonna try a Vintel Sauber valve soak next.

[bimmerboy12]

UPDATE TIME... I talked to my guy at Bavauto and he said the CPS is fine... 900 ohms is normal and this is a misprint in the Bentley manual. I believe him- he's had 17 E30s over the last couple decades. Anyways, I just went out and bought a vacuum gauge, and my car is reading 14.5 in Hg at idle. It wavers down 0.5 in Hg along with the idle. As soon as the car is turned off, the vacuum is gone.
Can anyone verify that this is normal?
Brian

ANOTHER UPDATE: I also just replaced the intake to throttle body breather hose and my pressure fuel line into the rail (it had some wetness around the clamp). No change, idle still sucks.

[bimmerboy12]

Original engine, never pulled. Only 121,000 miles. I just checked the receipt and it says I purchased the correct part, but I have no way of verifying that they sent the right part as I don't have the original packaging. I will have a chat with my guy at bavarian and discuss, and will let you know what comes of it.
Keep in mind I performed this test with the engine somewhat hot... only been turned off for half an hour or so.