car shakes like a hot rod on idle

[ros74911]

hello, all. recently tuned it up. how can i smooth out the car again? idle is perfect. it just shakes like a hot rod on stop? what to do? help!!!! thanks in advance.

[euro911sc]

Sounds like you are down a cyl... If it did not do this prior to tune up then take it back to where ever and tell them something is amiss. Your car should be smooth like glass unless you put in Solid mounts...?

It may be a simple loose spark plug wire... or a bad plug.

If you did the tune up... well ya made an error along the way somewhere. If you did the valves then take the covers off and recheck each one in two separate runs (don't just measure twice in a row, do the whole engine, then start ALL over and do it again and see if its the same) Something could be loose once, but not twice...

If you changed the timing or the mixture or any of the fuel system, well, you may be missing a loose hose or something. or maybe some injector gave up the ghost.

If you have a DME car... I don't think it would be a CPU related issue as when they have problems you usually don't run anywhere at all.

*shrug*

Start crossing things off the list

Best regards,

Michael

[ros74911]

thanks, michael for the tip. yes, i did it myself. i'll recheck the valves. no dme on it. i'll double check everything. i have been driving for over a week now. i thought it'll go away. is it safe to drive even the car shakes? please advise. thanks again.

[jlex]

Don't go thru the valves again right away.... The old adage is that when faced with multiple possibilities, the simplest is probably the right one.
Look again at your plug wires & make sure they haven't been crossed. I'm betting that you damaged a wire's insulation when you worked on it & it's shorting out against the engine tin.
Tonight when it's dark, start the car up & look into the dark engine compartment as its idling.... I'm willing to bet you're going to see where a spark plug wire is shorting out by seeing sparks.
If you can't see any sparks, a wire might be broken internally. Check each wire's resistance to make sure you didn't break one during the tune up. Lastly, if you're sure the wires are okay, then pull the plugs & inspect them... could be a cracked one.
regards,
jlex.

[ros74911]

thank you, jlex. i'll take your advise on it. check the wire plugs then the plugs itself. thanks.

[marmot]

Originally posted by ros74911
it just shakes like a hot rod on stop?

Sweet! Blub Blub Blub....

[ros74911]

yeah, thanks a lot. ur funny.