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IXLOR8 · Joined: 05 Jul 2005 Posts: 49

The car when starting cold runs very well and smooth. After warm up the idle will drop to 975 RPMs. Timing is right on. I will get a miss in the engine. It is not all that bad. (It sound like a cam lobe)

I do not quite understand why it will run smoother when it is cold, then when warmed up it will be a little rougher. Too lean?

Spark plug gap .028

Any ideas? I have not touched the mixture control setting, only the idle screw and timing. Idle at 975.

What size MM allen wrench is needed for mixture? 3MM? Very small adjustments?

Anybody with any ideas?
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Wisconsin

Lizard · Posted: Sat Aug 20, 2005 2:21 pm Post subject:

the air fuel mix requires a 3mm LONG handle allen key yes,
I would first replace the ign wires, cap rotor, and spark plugs if you havent, after that possibly have the air fuel mix checked, however I would recommend that you might think about having the injectors cleaned, or replaced, but of course pull them out and check the spray pattern in glass bottles by bridging the fuel pump and manually operating the air fuel meter plate.
I bet that 1 probably isnt 100% if you have already done the ign,
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3 928s,

IXLOR8 · Joined: 05 Jul 2005 Posts: 49

Lizard · Posted: Sun Aug 21, 2005 4:04 am Post subject:

ok the next easiest thing to check is to remove a little "window" off the distributor and spray some white lithium grease, this is for the mechanic advance and it can get abit sticky in there.

I would still recommend that you test the injectors spray, as it doesnt take much to make them mess up, if 1 isnt 100% swap it to another line and see if it follows the injector, if it doesnt then your dizzy is needing some attention
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3 928s,

IXLOR8 · Joined: 05 Jul 2005 Posts: 49

I ended up tweeking the mixture. It was a little too bit lean. The idle is smooth now. It drives very well. My next step is to take it in and have it adjusted by a professional.

The CIS is quite touchy.

Thanks for all your help.
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Wisconsin

tj924 · Posted: Sun Aug 21, 2005 9:46 am Post subject:

IXLOR8 · Joined: 05 Jul 2005 Posts: 49

All I used was a 3MM Hex head key. It was about 5" to 6" long. It had a 90 degree bend to it. It was nothing special. It worked well.
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Wisconsin

Lizard · Posted: Sun Aug 21, 2005 3:29 pm Post subject:

you could get the ones with the ball on the end and if it doesnt work then you could always just lop the end off it.
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3 928s,