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HartgeH26
07-21-2004, 10:14 PM
I recently put in a 288 catacam and head work. My engine was originally a Hartge H26 but the cam was wiped and the egine was a little tired, as the head was already worked by Hartge, is was more of a clean up and and not a crazy port job.


PROBLEM: the car doesn't seem to idle properly, when I come to a stop it drop to the point is almost stalls, and the idle seem really rough(like a mustang with engine work), the car was running lean, so we adjusted the AFM so it gives more fuel and I put a O2 sensor from a 3.5 so it would run richer. The plugs aren't white anymore but the idel is driving me nuts. I even bought a new idle control motor just in case.

Do I have too much cam, if so how is it hurting performance, the car seems to go well, I do 195km in 4th and top speed so far is 230-235KM.
I was doing those numbers before when I had a cam that was completly wiped and a head that was in need of some TLC.

ANY IDEAS AND COMMENTS WELCOMED.

Thanks

swartz
07-21-2004, 11:01 PM
try raising ur idle on the thottle body??? sorry im not much help

JSF252
07-22-2004, 12:16 AM
Does anyone else in this forum run a 288? That's got some lift to it, what's the lobe separation? Duration? I wouldn't think that a 288 would Idle that smooth anyhow. I know this is a different engine all together, but my cousin has a '70 SS Nova (350ci) with a 292 cam. That engine sounds like a box of rocks, and is no where near smooth. In fact I think it's too much cam, as his power brakes dont function properly (no vaccum) and he doesn't have the correct stall converter. I swear I read somewhere that the 288 was for track use, as the idle would be very rough.
Any how if you dont mind the car idleing a little higher, just bump it up a couple hundered RPM, and it will smooth out. This isn't the right way to do it, but if you want smooth idleing, I think it's your only hope.
Well I forgot to ask this, but did the engine have a 288 before you did the "refreshening"? If it did, then something is wrong, and your on the right track to fixing it. If the car didn't have a 288, and now it's "loping"..... it's probably the cam.
Just my $.02
Josh F.

x628x
07-22-2004, 01:10 AM
tri flow has a 288 i believe.

TriFlow
07-22-2004, 11:36 AM
:D

Has anyone done what he's done to his AFM?? Also has anyone seen on a e30 or used a 535 O2 sensor?? This is the first I've seen of these ideas in all my years of foruming..

I love my car when it almost stalls and I love the idle sounds like a v8..

I was told by a very good bmw mechanic to never let it idle to long cause over time it will damage engine parts. Rocker arms probaly seeing as how I'm on my 3rd set and all..

bimmerjim®
07-22-2004, 12:07 PM
do you know the overlap or duration of your cam? 288 realy isnt huge, stock is something like 260

when i had my 290 290 112 cam, it didnt have a hard time staying idleing. idle was lopey, but not harsh.

i would look for a vacume leak, or you might possibly need to disable your idle controll valve and open the tb with an idle screw and set the idle to 1200 rpm.

TriFlow
07-22-2004, 02:15 PM
do you know the overlap or duration of your cam? 288 realy isnt huge, stock is something like 260

when i had my 290 290 112 cam, it didnt have a hard time staying idleing. idle was lopey, but not harsh.

i would look for a vacume leak, or you might possibly need to disable your idle controll valve and open the tb with an idle screw and set the idle to 1200 rpm.

Vaccume leak forgot about that one :(

TriFlow
08-02-2004, 10:55 AM
I have the fix to your problem...


Do you have a cone filter??


I just went from cone back to the airbox. Huge difference in idle.. much smoother no more near staling.. Also another thing that made a huge difference was that I cleaned the ICV Idle control valve runs so smooth now.. No idle problem after you do these 2 things...

swartz
08-02-2004, 12:17 PM
i would def say raise the idle a tad with the screw on ur throttle body. that will deff help. and do check ur icv

65Matt
08-03-2004, 06:32 AM
Check your throttle position sensor on the bottom side of the throttle body. Mine was not adjusted correctly, so it wasn't 'telling' the computer to open the ICV. It was idling very rough and hard to start.