engine stuttering

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Berry
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engine stuttering

Post by Berry »

hi
the engine stutters sometimes when idling. only after some minutes driving. what could be the problem?
thanks!


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Asylum
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Re: engine stuttering

Post by Asylum »

TCC. Unplug it.
Square plug on the trans right about below the air box.


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Berry
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Re: engine stuttering

Post by Berry »

thanks eric!
this one?
plug1.jpg
I managed to tilt it up, but the plug is still stucked in the trans
plug2.jpg
how can I unplug it without to break it?


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Asylum
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Re: engine stuttering

Post by Asylum »

There is a clip on it.
I forget but just release the little lever thingy and it will pull off.


Eric

Asylum Motorsports
"Where we're not happy 'til YOU'RE not happy!






'91 California Quad (Gone with just a bit of "Seller's Remorse".)
'92 3500 GT gone and not really missed. It was fun. Documented 13.47 N/A.
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Berry
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Re: engine stuttering

Post by Berry »

yeah one clip I already released. is there a second one?


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Asylum
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Re: engine stuttering

Post by Asylum »

May be two sided. I forget, sorry.
Or just cut the damn thing, Pain in the ass as it is!!


Eric

Asylum Motorsports
"Where we're not happy 'til YOU'RE not happy!






'91 California Quad (Gone with just a bit of "Seller's Remorse".)
'92 3500 GT gone and not really missed. It was fun. Documented 13.47 N/A.
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themixer
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Re: engine stuttering

Post by themixer »

its hard to tell but it could be as simple as a dirty throttle body the tcc is normally a problem when slowing down from higher speed the car will just completely stall.


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Berry
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AW: engine stuttering

Post by Berry »

Thank you guys I will check both things and report later.


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Berry
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Re: engine stuttering

Post by Berry »

eric I unplugged the tcc. the engine is still vibrating when idling @700 RPM and its getting stronger. maybe a kind of vacuum problem?
my mechanic said that there could also be a problem with the compression.
what should I do next?


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Ozzwoman9
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engine stuttering

Post by Ozzwoman9 »

If u have oily spark plugs then I think you have your answer.


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themixer
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Re: engine stuttering

Post by themixer »

before wasting any time on doing anything else, do a compression test. I have had a stumble in my idle and i replaced everything looking for it. Now its going to the dealer and i fear it will need some major work. Better to get the test done now before doing like i did and replacing the plugs, wires, icm, iac, vacuum harness, coilpacks, CPS, CTS, O2, ECU, injectors for no reason. it could be as simple as a burnt valve


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Berry
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Re: engine stuttering

Post by Berry »

for a compression test I should take out all 6 injectors and spark plugs and put measurement instruments in. right?


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Money pit Beretta
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Re: engine stuttering

Post by Money pit Beretta »

Correct. Please post the numbers that you find.


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93 3.1L
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Re: engine stuttering

Post by 93 3.1L »

Berry wrote:for a compression test I should take out all 6 injectors and spark plugs and put measurement instruments in. right?
You do not have to remove the injectors.
Only remove all 6 spark plugs,
Find a way to block the trottle body wide open
Unhook the wires plugs going to the icm
Kill the fuel pump
Hook a compression gauge and crank until needle on gauge stops (or when you hear the engine turn 4-5 times)
Do on each cylinder and write down the numbers.


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Berry
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Re: engine stuttering

Post by Berry »

alright I did the test.
I made it in a DIY-garage
and I only removed the spark plugs
nothing else. then I put a compression
gauge into the holes one after another.
from passengerside rear to driverside front
cyl 1 has 8 bar
cyl 3 has 7 bar
cyl 5 has 8 bar (the one with the oily spark plug)
cyl 2 has 9 bar
cyl 4 has 8.5 bar
cyl 6 has 9 bar
so nothing special.

other things I've done:
I opened the egr. it was already very clean!
throttle body still clean. intake has only
little bit oil.

tcc unplugging I mentioned before
didnt change anything at all.

I changed the oil a week ago. it was
after a year black like coffee.

I sprayed the whole engine. no leaks!

and: I cleaned the pvc valve.
it rattles when I shaked it. seems to be ok.

my retta has still rough idle more and more. it shakes
every three or five seconds in N. it shakes also when I brake sometimes in D or R.

what could be else the problem? ignition
electronics (too high resistance?) or some exhaust issues? ecm failure?
problems with the clutch of the auto?
blown head gasket?
maybe I should check the errorcodes. I have OBD1 and
no idea how to do this...not yet

any suggestions?


...cruising
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