surging idle

[ZX-14]

The surging gets pretty bad once warmed up. It dies sometimes when I brake. Sometimes the car is difficult to start, when warmed up. I'm guessing that the accumulator is part of the starting problem.

Anything else I should look for?

Thanks guys

[Silverbullet]

Wow, I bet our cars were made on the same day. There is a lot it could be... the accumulator is easy to test... could also be the fuel distributor... injectors..

[cdrusn]

Sounds like you have a vacuum leak, that would be a good place to start. Use the vacuum routing label on the engine compt. lid to trace each hose and check for a crack or loose connection.

[David T]

The accumulator will not affect the quality of the idle. It will make it difficult to start the motor when hot. The typical causes of a bad idle include old, worn, defective:
ignition wires
distributer cap
rotor
injectors
spark plugs
hoses and seals causing vacuum leaks
The Lambda system not functioning properly and all of the adjustments "out of whack".
The idle motor sticking and/or leaking
The reluctor coil in the distributer not gapped evenly all around. It is usually multiple causes, not just one of these.
David Teitelbaum

[rothsean]

Also, make sure that the hole is plugged just in front of the fuel distributor. My car was idling terrible and chasing RPM, then I plugged it with my finger and it ran great, so then I plugged it with the correct plug...

[OverlandMan]

Also, make sure that the hole is plugged just in front of the fuel distributor. My car was idling terrible and chasing RPM, then I plugged it with my finger and it ran great, so then I plugged it with the correct plug...

Got a pic?

[Ron]

Got a pic?
It's the yellow thingy in the upper right corner in this pic:
http://dmctalk.org/attachment.php?attachmentid=12565&d=1345127104

There are several styles around, the originals are a flush aluminum plug (PITA to remove), with most of them similar to #14 here (Note there are two #14s in the list):
http://store.delorean.com/c-334-1-4-1-air-induction-system.aspx

[Kenny_Z]

Shortly after I purchased Red I chased an issue that sounds like what you described. I swapped plugs, rotor, cap, wires, and coil. I was doing those anyway as part of newly purchased car maintenance but they did not solve the problem. Turns out the engine's ground was failing when it warmed up. I installed a new ground from the battery to the transmission and engine to the frame and my problems stopped. She hunts a little when the temperatures are low but once she warms up I don't have hunting or stalling.

[ZX-14]

Thanks, will check a few things before replacing things at random.

I held the rpms around 2500 and it has a "miss" or bump that interruptes about every 3-4 seconds, its like clockwork. Exactly the same rate it interrupts the idle. During braking, you can feel the car surging itself while comming to a stop.

[lazabby]

Thanks, will check a few things before replacing things at random.

I held the rpms around 2500 and it has a "miss" or bump that interruptes about every 3-4 seconds, its like clockwork. Exactly the same rate it interrupts the idle. During braking, you can feel the car surging itself while comming to a stop.

I've had that issue in the past where the idle was never quite smooth. There would be a slight drop every 3-4 seconds like clockwork. I never figured out what caused it.

[Spittybug]

Are you an automatic by any chance? Just a theory.......

[ZX-14]

Yes, it's an auto.