HEy
Today my car started acting really weird. I drove it around all morning...remembering to properly wwarm it up and cool it down. All went well. THe n at about 3 i left my friends house. I was driving it somewhat hard. On the interstate, in 5th gear, it would not pass 3k rpms! No matter how hard i hit the gas..it would like try to go, then stuble and stay steady at 3k rpms. THe non the offramp i wnr down to 4th, still could not pass 3k rpms. As i neared a red light near my house idle started feeling rough and was bouncing in the 700-800 rpm rangte. So i kept the throttle on to make sure i could get it home. Luckily i make it home. As itidlede extrmely rough and bounced in the 500-700 rpm range and finally sputtered and died within about 30 seconds. I started it back up again, only for the same thing to happen. I dont know what is wrong with it. THink it may be a blown engine? I will check all the fluids after i get off work tonight and my car is cold. ANy suggestions or insights will be greatly appreciated! Thanks alot for your help!

-Jeff

 

I have the idle problem but it never dies at idle just real rough. I was able to turn the idle up a little and it is better but still doesn't seem right. I just got my 7 so I think it needs new plugs and wires, fuel filter and some other maintence things that were possible neglected. Also notice that sometimes boost will not go past 0 drive a little more and it goes back to normal boost. Any ideas on the problem?

 

It could be a blown apex seal. Before I would panic though, I'd see what diagnostic codes are coming up

 

what is your vaccum at idle? if its around 10inhg or under your screwed, but if its still at 15-20 i dont think you popped your engine yet. check the boost sensor, its on the firewall near the driver side. what are your mods? check the vaccum lines comming off the primary turbo, especially the waste gate one. in fact, check all the vaccum lines.

is any smoke comming out of the engine bay or tailpipe, if so what color?

when cool, check coolant level via the ast tank or refill tank, not the overflow one.

What was the temp. like at the time this started to happen?

check the diagnostic codes using http://www.scuderiaciriani.com/rx7/engine_codes.html
Note: do not start engine when you have the wire in terminals named "TEN" and "GND"!!!

good luck

 

The O2/Map? Sensor (forgot which one it is) is a small black box right in front of the driver side firewall. It has a tube that sticks out from the bottom that likes to come loose...the idle and then dying problem sounds like it could be that. But I don't know about the 3k rpm problem.

 

when it idles really rough(right before it dies) it spurts out puffs of black smoke. just consistent small puffs. I have a pettit ast and greddy boostr gauge. I recently installed new plugs, newoil filter, oil , and a new fuel filter. About 800 miles ago. My boost gauge is metric, so would you happen to know a conversion? Thanks alot for the help guys. I am going to take a long good look into things tomorrow and will post what i find. It'll help if yall can keep in touch after i post what i find. Thanks again for all the help!


-Jeff

 

check the MAP sensor..It is the little black box on firewall with vacuum going to the back of the intake manifold. If it is not connected, the computer will sent tons of fuel through the system and it wont idle correctly. You can also purchase an inexpensive compression tester at autozone for under $30 bucks. Test the rear housing first. It is usually the one that pops first if it is a seal.

 

Jeff,

Check the hoses and piping between the compressor of the turbos and the intercooler. Also check the hoses and piping between the intercooler and the throttle body.

It sounds like you have a massive vacuum leak.
A blown engine could still go over 3krpm, mine did.
However, when I had my Turbo II, I blew the Intercooler to Throttle Body hose clamp loose and it did the exact same thing you've described.

Did you hear any kind of "poof" when you drove it hard?
How much boost did you run when you ran it hard?

The puffs of black smoke sound like fuel. Does it smell of fuel?

Try to rule out other things before jumping to conclusion that you blew the engine. To be sure, you can do an engine compression check. People get very paranoid about rotary engines and assume the worst before looking into the matter. If you don't feel confident that you are mechanically inclined, please take it to a reputable mechanic.

J

 

Apparently my brain crapped out on me and i forgot what a metric boost gauge reads, is it kg/cm^2 or mmHG? anyways 1 inhg= 0.03453kg/cm^2=25.40 mmHG

Good luck

 

well....i just went out to fix my car and sure enough the little vacuum hose under the boost sensor had popped off. Wht a relief, now i can once again sleep at night. Thanks alot for all the help! i dont know what i would have done. I checked my idle @ vacuum and its at 19.6 inhg. thanks again.




-Jeff

 

It seems like everyone's hose pops off and scares the crap out of everyone hehe, it happened to my brother too. In anycase, I think your engine is pretty health with 19inhg (usual vaccum is about 16inhg)

Good job on finding the problem

P.S. Ziptie it!

 

Told ya so!But seriously, the same thing happened to my FD and freaked the hell out of me.

 

symptoms of a blown motor: over 60K miles.

*ducking, running*