Zoomspeed

I've noticed that eletrical load seems to effect my idel alot.

My idle is already kinda low (600-700RPM). I think thats due to a vac leak somewhere becasue I'm only reading ~12 inHG at idle, but thats another topic.

Well, I always noticed that when I turn the A/c on or get the fans to turn on, my idle dips to about 500 RPM then kinda struggles then it goes back up to ~700RPM.

I also noticed that when I'm idleing in my garage (or anywhere else ) that when I press my brake my RPMs dip by about 100RPM but dont' climb back up. The samethig happens when I operate my power windows or sunroof. What really worried me is that this afternoon when I was parking my car. I was closing both my windows, sunroof, and I had my foot on the brake all at the saem time and my idle went all the way down to 200-300RPM.

I don't think this is really hurting anything, but I want to fix it anyway. Any ideas on whats wrong and how to fix it?

Thanks for any help.
Hoainam

Zoomspeed

anyone have any ideas?

badass7

EXACTLY the same thing that happened to me. Changed plugs and wires and it went away !! Even if you turn the steering wheel (load) it has the same effect correct?? Try that and let me know what happened. BTW, if you go to Napa you can get Platinum NGK plugs for $8.50 a piece !! Cheaper than the stockers from the dealership.

badass7

IF, problems persist, it may be your intake manifold gasket which also gave me those symptoms before I had it changed at 78k miles.

Zoomspeed

Yup the sterring does it too. I hope its the plugs and wires cuz I'm about to change them soon anyway. Thanks

badass7

Get some Taylor Pro wires from Summitracing.com They fit absolutely perfect and have lasted close to 2 yrs. with no problems. If your idle keeps doing what it's doing after the "tune up" it's definitely your Intake manifold gasket. My car is a '93 and they still used that cheap cardboard type gasket. I believe they changed it in '94. So, if you have a '94 you can rule that out. Keep me posted.

Zoomspeed

the manifold gasket your referring too is the one between the intake plenum and the manifold right?

CYM TKT

iTrader: (4)

I am having all the symptoms you have but I also seems to have lower than usual boost. do you have this problem too? my vac is around 12-14 like yours and boost is a round 9 psi

7-sins

My idle has been good one minute then bad the next. It is starting to worry me. I have close to the same symptoms... but other times the car will start then die, start then die, ect. Also if I push the clutch in at somewhat of a high RPM range it might die. Other days it runs perfect except around 1k rpms. I have checked for leaks in my gaskets... sprayed carb cleaner and nothing. I also recently replaced plugs & wires.

mightyslash

It could be the compression?

7-sins

I really hope not... less than 10k on the motor.

MastaCow

I have a similar idle problem lately-I'm hoping its the plugs/wires. I'm changing them this week.

CYM TKT

iTrader: (4)

plugs did not fix mine, wires are still good i believe. also my car will do the start and die thing on occasion as well. I think it is just a bad solenoid in the rats nest (had a similar problem about 6 months ago), intake manifold is coming off today so we can check. I will let you know if that is it.

djantlive

Rotary idle problems are a bitch to diagnose. There could be so many different things.

You guys are talking about the Lower Intake Manifold gasket I think. It deep down in the engine to the passenger side. Replacement of that requires removal of turbos, airbox - quite a big job.

My mechanic told me that I have a leak in the LIM. I sprayed carb cleaner but I don't see any RPM change. He adjusted the idle so I don't stall on hot days. It now idles at 15k in N and 900 in gear. I contacted Dave @ KD rotary and he said if it's not a big leak, it's okay.

Bad TPS, Plugs/Wire, Battery ground wire, engine ground wire, bad solenoid, clogged fuel filter, dirty injectors, faulty ecu, bad battery or alternator, LIM leak, loose vac hose can all be part of the problem. You just gotta check/replace them one by one (unless you are a real rotary mechanic.)

Zoomspeed

I hope its not compression, I only have about 12k on my motor. My car starts just fine though. It idles smooth too. Its just when there is a load the RPM fluctuates.

Zoomspeed

well, the plugs and wires didn't fix it for me. I guess I'll have to start poking around.

Another thing I noticed is that with the headlights on, they actaully dim a bit when I use the power windows or the sunroof. Any more ideas on what this could be?

7-sins

I just drove my car today... only stalled once then didn't act up. I wish this crap wouldn't be so weird.