I got a 93' with a single turbo, microtech LT 8, AVC-R, custom fuel system. The car has been in the shop for almost 6 years(whole nother story! not many people know what they're doing in wahington!) Just got the car back 2 weeks ago running great, went around a corner and it started missing horribly. Checked for noticable vacuum leaks or anything else. Nothing was found changed the plugs, they were black but made no difference with new. Started it this morning and it free revs great! once it warms up barely keep it running but will idle and starts really hard. When driving not under load A/F is at 13.3 and try to give it gas jumps down to 9.9.

Anybody have any ideas? getting tired of throwing money at it!

Thanks!

 

Was it tuned when it got out of the shop, and what shop did the work just curious. If it was tuned then they didnt do a very good job 9.9 is pushin it on the rich side of things. Does it only have the issue when you are on the gas. Also if you list you mods it can help us figure out your problem a little bit more.

 

Gary at Extreme Performance, seems to really know his stuff but live about 2 hours away. It was tuned by him and ran really good had all kinds of power but was only tuned to 7 psi until it breaks in. I have a apexi RX6 single turbo, Microtec LT8 1300cc secondaries, 2 cycle oil injector, A1000 pump with an6 feed and an8 return with aeromotve fuel pressure regulator, HKS twin power, street port with 3mm seals. The A/F was in the 11.6 range until I went around a corner yesterday and all of a sudden the A/F is all over the place. When I start it the vacuum is at 18psi but then you rev it and when it goes back to an idle sometimes it runs at 14 psi vacuum and misses not sure why it makes a difference when it's warmed up...

 

Where do you get your tuning done?

 

Vacuum is measured in inches of mercury, not psi.

What rpm are you seeing the 18 inches vacuum at? Is your idle rpm higher when it's cold (ie 3000 as per the stock AWS system)?

When you went around the corner were you low on gas?

 

so what exactly is the problem?

An idle problem once its warmed up? a more descriptive problem might help.

It is indeed hard finding a good place to properly work and mod these cars... I've seen some total crap coming from places that are supposed to be good shops.

 

Two things spring to mind:
1. tire rubbed thru inner fender and wiring harness on left side - do you have bigger aftermarket wheels and tires? If so, that is fairly common.
2. something came loose or fell off during the cornering - check all vacuum hoses and electrical connectors again (even tho you said you already checked).

 

my cold idle is about 1400 and my warm is set at 1200 otherwise I kill it to easy with the 6 puck clutch. It has no power and misses really bad when you give it any gas at any RPM but its hard to get it above 4000rpm while driving.

It idles fine it's once you give it any gas..

I had the car at 2 shops that really screwed me over 1 blew it up and then went bankrupt! really set me back! and the other just didn't know enough about rotaries to diagnose the problem.

 

Steve Kan and Chuck Westbrook are excellent tuning resources. Steve kan frequently does tuning events when a bunch of people get together to fly him in and tune. Check your regional forums for that.

If the kind of problems you are having are beyond your abilities, I'd seriously consider trailering the car to a good shop even it means going out of state. Also look in the regional forums in your area for recommendations on places.

The forum is agreat resource and there is lots of people and info here that you can search for to help your problems. Sometimes that only gets you so far.

 

Does it feel choppy at low rpms, like pulling away from a stop in first gear? 14 inches at 1200 rpms is very low, even in a ported motor. What was the vacuum before this mishap?

 

how old is the gas in your tank?

 

That's why I am all for doing my own work. If something goes wrong, it'll be 100 times easier to troubleshoot. You'll also save a ton of money...

 

I would assume the shop didnt tune the car correctly, you are running really rich which is why im thinking you're missing a whole lot, too much fuel is being dumped into the combustion chamber.

I would check obvious things first anyway. Check TPS readings.

Change your gas, maybe change your fuel filter if you havent already.

Damn 6 years in the shop and its still not right? I feel sorry for you. I hope you get it back straight soon.

 

Gas is maybe a week old.. The thing about it is it was running great A/F in the 11s under boost now it just goes way rich all of a sudden... Can Microtech loose it's program and have to be redone?

 

.

 

Change the leading plugs to 10.5s

 

car was at 18 at an idle before and now idles rough and has low vacuum sometimes. when it idles good it does go back to the 18 inches. Seams to run alot better when cold.

It is very choppy while driving or pulling away.

 

Buy a $20.00 compression tester and follow the instructions on www.rotaryresurrection.com. Once you rule out compression then start looking into other things. I know it is hard to imagine it would be compression already, but a bad tune can do that in a hurry.

 

hardly anyone has luck with microtech here in washington