Slight hesitating pulling away from a stand still.

[SIMid]

Just noticed the last couple of times I have driven the car, I noticed a very slight (occassional) hesitate on the engine as I pull away from a stand still.

I did get the distributor and rotar changed by my mechanic over a month ago (new sparks 8 months ago) and he also removed the intake to get access to it. When I picked it up, all is good. Only just recently she started this little hiccup.

She wont stall, just a very slight pause taking off, not enough for the engine revs to drop too drastically. This wont happen all the time, only the occasional take off. It happens with the A/C on or off.

Thought I'll ask before anything serious happens (like being stranded on the side of the road).

Any ideas?

[Jonathan]

If it's the kind of hesitation where pressing the gas doesn't immediately translate into the engine speeding up, you might have developed some slack in this:

http://store.delorean.com/p-6409-rod-assy-throttle.aspx

It's what goes between the throttle cable spool and the butterfly valves lever arm. The sockets on the two ends can get sloppy or the linkage itself may require a length adjustment. If you take both ends off, you can adjust it almost infinitely for length. If you only get the end off near the spool, you can only adjust the length via one complete rotation (so that the sockets line up again when you reinstall).

[NightFlyer]

She wont stall, just a very slight pause taking off, not enough for the engine revs to drop too drastically. This wont happen all the time, only the occasional take off. It happens with the A/C on or off.

Does it only seam to happen when the engine is cold, such as within the first several minutes after a cold start-up?

[SIMid]

Jonathan, it only happens occassionally and only when warmed up that I had noticed. If there was some slack, wouldn't it be like it all the time? Just trying to think it through.

Does it only seam to happen when the engine is cold, such as within the first several minutes after a cold start-up?

No, strangely when the engine has warmed up. No issues starting hot or cold.

[NightFlyer]

Jonathan, it only happens occassionally and only when warmed up that I had noticed. If there was some slack, wouldn't it be like it all the time? Just trying to think it through.

No, strangely when the engine has warmed up. No issues starting hot or cold.

As opposed to a slacked throttle cable, what about a sticky/un-lubricated throttle cable linkages. As the existing lubricant heats up, it loses its viscosity and causes stickiness in the operation of the cable and linkages.

My best guess at this point....

[SIMid]

As opposed to a slacked throttle cable, what about a sticky/un-lubricated throttle cable linkages. As the existing lubricant heats up, it loses its viscosity and causes stickiness in the operation of the cable and linkages.

My best guess at this point....

I might get my mechanic friend to take a look at it. Sounds possible.

[Bitsyncmaster]

Most of the time, hesitation is caused by improper mixture (AFR). Have you had the mixture adjusted with a dwell meter? You adjust it with a warmed up engine.

[SIMid]

Most of the time, hesitation is caused by improper mixture (AFR). Have you had the mixture adjusted with a dwell meter? You adjust it with a warmed up engine.

I have not touched it, unless my mechanic fiddled with it when he took the intake off to change the Cap and Rotor. Next time I take it out, I'll have a fiddle with it. I heard even a quarter of a turn causes drastic changes.

Thanks for the suggestion Dave.

[DMCMW Dave]

I have not touched it, unless my mechanic fiddled with it when he took the intake off to change the Cap and Rotor. Next time I take it out, I'll have a fiddle with it. I heard even a quarter of a turn causes drastic changes.

Thanks for the suggestion Dave.

Yeah, even an 8th of a turn is drastic. If he fixed any vacuum or unmetered air leaks in the process of R&Ring the intake, it would change the required setting as well.

[David T]

Yeah, even an 8th of a turn is drastic. If he fixed any vacuum or unmetered air leaks in the process of R&Ring the intake, it would change the required setting as well.

If it just started doing this (and you didn't touch anything recently) one of the most likely causes is vacuum leaks. Especially since you mention the intake was removed. Plenty of opportunities to create or develop a vacuum leak. Another possibility is the gas. Did you recently put gas in?