After a short "1/4 mile" but hard acceleration run, I noticed that after the freeway exit, I had a rough idle and low vacuum (10 psi vs. 16 psi).

I pulled into my destination, with the rough idle and low vacuum, and let the car idle for 3-minutes even though it was rough.

Came back out in 5-minutes, and car would NOT start normally.

I floored the accelerator, the engine started, but after I lifted off the accelerator, the engine died.

I checked for loose vacuum lines including the MAP/boost sensor (line replaced 1-week ago), and found none.
I checked all fuses and they were OK.

I re-started with the accelerator floored, kept the RPMs at 1800 for 5-minutes, and was able to drive the car home (2-miles).

In the driveway, the idle was rough at 700 RPMs, BUT the engine did NOT die at idle.

The night before I noticed the turbo-to-intercooler clamp had moved, so I tightened it up, which means it was too loose.

My mods include:

1) Efini Y-pipe (replaced all gaskets w/new updated metal gaskets)
2) gutted down-pipe
3) CAT-back muffler
4) M2 Stage III ECU

I have the stock airbox, and my boost meter when hooked-up to the UIM, reads 12-10-12. The engine has 95K miles on it.

Just a week ago, I drove the car even harder, but didn't experience this, however I didn't have the turbo-to-intercooler coupler on very tight.

I'm going to get a compression gauge to check for a blow APEX seal (can it detect a cracked APEX seal).

Anything else to check ?

I did not change the stock paper LIM gasket to the metal one since I did not take it out.

Thanks in advance,
:-) neil

1993 Touring 95K miles

 

Sounds like a blown motor to me but confirm that with the compression test.

 

95,000 miles on it.. Sounds blown to me.

 

blown motor sounds obvious to me...def do a compression test before anything else..

 

now you get to learn how to build an engine.

 

I let the car sit for 2-hours in the garage.

Car started right up.

Idles at 700 RPM, doesn't die, but seems rough.

When I shut down the enginem, I hear a "psssss" sound.

Blown engine ?

Now do I rebuild this one, or convert my engine from an automatic to stick-shift duty ? It's been sitting for 2-years, but has less than 100-miles on it!

:-) neil

 

my fd has 90k miles on it. i better treat it nice cuz i dont have the money for a new engine right now

 

psssssss...as in a trashed turbine wheel slowing down??

take the spark plugs out and have a friend turn the key with the fuel pump fuse pulled and listen for consistent whooshes.

 

but yes, if you pull the engine...pull the tranny too. (I have a 95 manual ECU) get an RZ tranny...maybe a reman if you don't want to rebuild it yourself...do some research and start wiring for the ECU swap...buy a single turbo, etc...

 

it doesnt sound good but it cooould be something else
the easiest way is what was said above take out 1 leading plug at a time and turn it over it should sound exactly the same 3 times in a row for each rotor

 

Sounds blown, I went through this a few months ago, just consider it done.

X...

 

Whenever you have a problem like this, first thing to do is a compression test. That will tell you for certain if it's the motor. It literally could be a zillion things, but a compression test will rule out the engine.

Go spend $30 on a compression tester and do a search on how to do the test. It's relatively simple, and will let you know what you need to know. No sense making plans on what you want to do with the engine and stuff until you know that's the problem. Could be something as dumb and simple as a bad plug wire or an injector plug that came off.

Dale

 

Yep. You won't know for sure until you CT it.

But 95k man, that's a pretty good run of time don't you think? I say thumbs up. If it's blown - it's blown. Just part of the learning process; it's not like the car is changed in any real way. This is what rebuild kits and procedures are for.

 

Yep, blown apex seals on the front rotor.

Rear was OK.

Time to put my spare to the test.

BTW: which is easier:

1) pull out engine with tranny attached;
2) drop tranny first, then pull-out engine
3) just pull-out engine leaving tranny in car

I have access to an engine hoist.

Thanks,
:-) neil

 

sorry to hear man

but at least when you build it back up, you build it stronger and better

i would take out tranny before you pull engine out..

 

Are you sure you broke an apex? Maybe your hard run just fused some carbon and stuck one of the apex seals to the front rotor. I'm suggesting a similar situation to what usually causes the rotary to flood. You know, after 95K miles you have little to loose trying to 'free up' a possibly stuck seal. Just a though before having to pull your engine.

It might not be that long before I'm facing the same situation. My one-owner FD now has almost 94K miles on the original engine. It was running fine tonight when I shut it off, but who knows about tomorrow morning…

 

After grenading 4 engines that sounds like it's blown.

 

from the symptoms, it doesn't sound blown to me. a compression check goes differently for rotary motors (compared to a piston motor). if the motor starts right up after only 1 and at the most 2 cranks, compression is still good, showing signs that the apex seals ARE STILL holding up the usable compression.

it sounds like your fried your ignition system. check wires, coils, and plugs. it's very possible the rough idling is the result from running only on trailing (or leading). i am almost 90% sure that is the problem.

 

IMO, engine seperated from trans then pull only engine is the best way.

But there have been threads debating this in the past.

 

I've done it both ways and would have to agree that pulling the engine only is easier IMO as well.

 

agreed, detached the tranny when i pulled mine, piece of cake.
just don't forget to pull the release to let it go (engine manual)... the guy i put 'in charge' of tranny messed that one up!

as said before, there are tons of threads on this exact thing, this is just my opinion.

 

Eh i think that they are about the same. Pulling with the tranny makes it quicker, putting it back in with the tranny is harder then just the engine...

 

Should I just get some new plugs as well.

FWIW, we pulled the trailing plugs to check compression and the needle bounced twice to 60 psi, and once to 97 psi on the front rotor rotor.

On the rear rotor, the compression gauge's pointer bounced to 97 psi, three times.

We did this on a warm-up motor.

So how do i "free up" a stuck seal ? Just run it hard again ?

:-) neil

 

umm theres no stuck apex seal bro
the tips of it melted off

you could raise the idle a bit and continue driving it if it doesnt have a hard time starting.

 

Your compression test clearly points to one apex seal, but is it dead or just stuck?

I'm not saying this will correct your problem.

Pull the lower sparkplug on the front rotor, then using ATF in a squirt can and put several good pulls in through the plug opening, then bump the start and put ATF in, and repeat one more time. Let the car set overnight and then start. Expect LOTS of smoke so plan on keeping it running for a while, or take an easy drive. The ATF is vary high in detergents and might loosen the carbon, if that's really all that's wrong.