after an intense freeway run last night my car started having problems. i know it's most definitely the vac seal if my vac is reading at 12 on my boost guage. but also my idle dropped to around 600rpm. when i hold the rpm at regular idle, my vac reads a healthy 20. this morning when i started her up. everything was normal for about 10 minutes. idle was at 1.4-1.5 and my vac was koo too. good on coolant and oil. no oil leakage. after my car warmed up my idle went to **** again. i'm expecting the worse case scenario, but if someone can tell me otherwise, i'd love to hear your opinions or knowledge. i'm thinking maybe a hose could have fallen off or cracked. i'm somewhat new to the rotary game so i'm still takin in the nfo. also when the idle drops down, my car shakes. let me know what's up.

Andrew

 

Is the car hunting idle? Like going up and down between 600-1200 or what.....Give us a little more info. Also check your map sensor, a hard run can pop that hose off easily.

 

naw. it gets stuck at 600. which is also complimented with a weird smell. kinda like burnt clutch or oil. could the map sensor be a cause?

 

Check your double throttle?

Dave

 

double throttle? sorry. i'm still pretty newb when it comes to the mechanics.

 

also. i thought i was good on coolant, but it's at the bottom line. so possibly my coolant seal?

 

sounds like a chipped seal to me....it doesn't take much at all to cause the shaking, but you may not be losing much compression, and the car may still run pretty strong under boost

been there....done that....tried to imagine it was something else....it wasn't

 

and a chipped seal means i shouldn't be driving it hard though right? i heard that the pieces of the chipped seal could get into the turbos and eff em up. i just wonder if it's drivable while i muster up repair money or i should borrow a car for the time being.

 

Way too early to be jumping to conclusions about busted apex seals,,,,id check all the basic stuff out,,, check to see if any vacuume hoses have poped off,,, pull the spark plugs and have a look at them make sure they are all good (maybe clean or replace),,, try pull the ECU codes make sure there arent any electrical faults.

 

koo. i'll check up on everything suggested. so should i lay off driving it until i find a solution? or do you think it's safe for me to roll around in it as my transportation?

and i thought i'd get some flack for not knowing too much. thanks for making the forums comfortable :]

Andrew

 

after you do a compression check, if you determine you have a chipped seal, you should definitely not drive the car

 

it could be the radiator/cooling fans kicking in. my idle dips to ~600 when they turn on, and continues to be low until they shut off.

 

^Same here^

 

i don't think that's it. in any case. is there any manual anyone would like to suggest? i still haven't picked one up.

 

oh yeah.. check engine light is NOT on.

 

Does the vacuum needle oscillate at all while you are idling?

Where are you located?

 

What does it mean if the vacuum does oscillate?

 

I bet its the ignition. I am in the middle of diagnosing a idel problem as well, and miine bounces up and down between 690-760 at times and I seem to notice more haunting when I touch the ingtion coil harness...thats just mine though, I thnk your coisl might be done for.

 

:-( Oh well At least it isn't the motor. Mine is doing the same thing too only after I fixed my TPS Problem and now when I turn my lights on the idle problem goes away and the vacuum steadies out.

I need Spark Plug Wires I know that. I will more than likely get some MSD Coils to go along with it and the Grounding kit.

 

so gonna do all the inspection today. pick up some break/carb cleaner to check for a vac leak. try a map whack fix. theres ******* hella vac lines X\ . i don't really want to remove the extension manifold but since i'm not driving it for the time being, i have a desire to explore my engine.

it seems like it could be my o2 sensor as well. i'm taking any other diy suggestions. thanks guys. girls?

 

located in san jose california.

 

You mean Milpitas

 

If the car holds a consistent idle, and the vacuum is both lower than normal, and also has a regular oscillation to it, that is a sign of a chipped/cracked apex seal (irregular compression).

 

Interesting. Mine only started having problems after my TPS went crazy. After I fixed it my idle will stay up 1,500 or so. When I am stopped I can let out on the clutch a little to bring the idle down to 720 rpm's and it will lump about 15rpms, vacuum will stay steady then they will oscillate a little and the rpm's will jump back up to 1,200. I have adjusted it out to where I can't adjust the idle screw or the air bleed valve anymore. My vacuum is at 18-17 inches of mercury.

I think my problem lies elsewhere. I still have the vacuum lines from 1993 on there so I am going to change them out this weekend and see what happens. Plus I have no air pump on the car with the stock ECU.

 

just a note: vacuum readings don't mean a whole lot, you can have a very healthy ported engine with an open intake and 12" Hg at idle, it depends on several factors

if you are near stock, it may be a useful diagnostic tool, but the shaking is what tips me off to engine trouble, that means the balance is off...it sure isn't the O2 sensor lol