the infamous rough idle

21030 Views 23 Replies 9 Participants Last post by grkguy89, Aug 9, 2010

grkguy89

Discussion Starter · Jul 30, 2010

i swapped out my b234i for a b204r
and now have a rough idle with a vacuum at about 11-13 inHg
cant seem to find any vacuum leaks though
i checked engine timing and everything lined up
plus is seems like im running extremely rich at idle (i think this may be why my idle is rough)
ideas?
(ask me questions to narrow things down)

1 - 20 of 24 Posts

dan-the-kid

· #2 · Jul 30, 2010

check out the IAC?

grkguy89

Discussion Starter · #3 · Jul 30, 2010

cleaned it and tried two other known good ones (i mean they others worked fine on the other cars)
made no diff
even tried another MAP sensor and made no diff (i might try a new one tomorrow)

132417SAAB

· #4 · Jul 30, 2010

Is it the same tune? Could be over fueled now with the smaller displacement...

grkguy89

Discussion Starter · #5 · Jul 30, 2010 (Edited)

tried a stock ecu (stock turbo ecu) and my tuned ecu (matched to the hardware on the b204r; stage 4)

no difference

132417SAAB

· #6 · Jul 30, 2010

start the car and unplug the iac if its bad you should notice an improvement

grkguy89

Discussion Starter · #7 · Jul 30, 2010

if i unplug it it nearly stalls out, plug it back in and rpms shoot up for a second and then "idle" out
so its working, not necessarily working perfectly

grkguy89

Discussion Starter · #8 · Jul 31, 2010

im gonna order a new iac mon from my shop to try out just to be on the safe side
any other ideas though?

GenuineSaab

· #9 · Jul 31, 2010

The 2.3t broke?

Miss a ground wire on the intake manifold? IAC won't influence mixture.

PoisonBeef

· #10 · Jul 31, 2010

GenuineSaab said:
The 2.3t broke?

Miss a ground wire on the intake manifold? IAC won't influence mixture.

Um... what would happen if you missed this ground wire?

GenuineSaab

· #11 · Jul 31, 2010

PoisonBeef said:
Um... what would happen if you missed this ground wire?

There are power grounds and signal grounds. If you leave the signal ground floating this will bias the sensors. The power ground would make it hard for the injectors etc to function.

Check the signal ground.

grkguy89

Discussion Starter · #12 · Jul 31, 2010

GenuineSaab said:
The 2.3t broke?

Miss a ground wire on the intake manifold? IAC won't influence mixture.

nope, it didnt break
i reached a power ceiling on that setup and didnt want to invest anymore money since the b204 is much much easier to work with

in other word i had an itch for more (easy) power

ill check the grounds again to make sure

GenuineSaab

· #13 · Jul 31, 2010

grkguy89 said:
nope, it didnt break
i reached a power ceiling on that setup and didnt want to invest anymore money since the b204 is much much easier to work with

in other word i had an itch for more (easy) power

ill check the grounds again to make sure

You had a turbo manifold on it? Turbo cams would have helped some or different cam timing with stock 2.3i cams.

grkguy89

Discussion Starter · #14 · Aug 1, 2010 (Edited)

i was very impressed with how the car performed plus i never had a chance to dyno it with the td04 on it but i would guess around the 230whp ball park

its just that i wanted to get into something that would cost "less" to upgrade to get it to 300hp

hkayssi

· #15 · Aug 1, 2010

GenuineSaab said:
There are power grounds and signal grounds. If you leave the signal ground floating this will bias the sensors. The power ground would make it hard for the injectors etc to function. Check the signal ground.

OK, that might be the problem with my project car then. I know the engine was replaced at a certain point so that might be a definite possibility

Where would that ground be exactly Nick???

grkguy89

Discussion Starter · #16 · Aug 3, 2010

ok so here's the latest

my car still wont idle right
vac is at 11 in.Hg
on decel i barely hit 21 in.Hg so my car doesnt decel as it should when off the throttle

tech2 readings

at idle
tps is at 10.2%
timing at 3* (this is supposed to be at bout 10* right?)
and O2 reading all over the place

plugs look like things are running rich

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dan-the-kid

· #17 · Aug 3, 2010

I think timing should be around 6-8 degrees.

live2record

· #18 · Aug 3, 2010

rattle

I removed the insolation from under my hood and added a blowoff valve at the same time. About that time i started getting a rattle noise only audible from the inside of the car. Im new to saabs and hope this is related any ideas what it might be?

grkguy89

Discussion Starter · #19 · Aug 3, 2010

try starting a new thread bout your problem

try just look around the engine bay for anything loose... maybe use a stethoscope to try and isolate it
[/thread jack]

back to my problems now

live2record

· #20 · Aug 3, 2010

thanks

sorry thanks i will do that

1 - 20 of 24 Posts

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