is it possible to have a chunk of carbon stuck spinning around in the engine?

the guy i just bought my 7 from said he took it to a dealership and they diagnosed it as being a chunk of carbon is keeping the car from running correctly... and i dont remember ever hearing or reading about this problem... he also mentioned that it happened (the carbon) because he stored the car during the winter and your not supposed to (thats what he said)...

what else would cause my really rough running/ hard to start problems

car has 120k miles on her and was owned by an older man (probably wasnt beat on)

- flooded
- vaccume leak
- bad compression
- ?

edit: btw... happy 4th everyone!

 

hard starting can equal flooding, bad compression or a number of other culprits.

I would first start by getting a compression test done to see what you're working with.


And, I suppose carbon could be bouncing around inside your engine, however its more likely that if there was carbon loose in the motor it has found its way out by now either through an apex seal or simply out the exhaust.

 

yeah.. RX7 + older man who wont drive it hard = bad. Rotarys love to be beat on and abused, at least once in a while. There is probably carbon built up around the seals. Try takin it out for a drive, redline it 5 or 6 times...

 

He may mean that there is a stuck seal. This is generally due to carbon or corrosion. You can try to dissolve it using oil, carb cleaner or ATF (though ATF doesn't really attack carbon all that well) or just drive it and hope it frees itself up.

I assume this diagnosis is backed up with a low compression reading or a visual confirmation?

 

You can also do the water injection thing as a last ditch effort...

 

not even sure... he just told me that he took it to a dealship of some sort and they looked it over and told him what he told me... i still really havent had a chance to get under the hood cause of it being a holiday weekend...

 

what about using MMO?

think i might try that tomorrow... if i can get my battery recharged

 

MMO is not very good for this...You need something that dissolves carbon (if cabon is the problem).

 

like ATF? or?

 

He just made suggestions a few posts ago. He said oil or carb cleaner work best. The water trick was also mentioned, but I think its more of a preventative measure.

 

ATF doesn't touch carbon.

 

do the water trick, it effectively steam cleans the engine. you may also want to try pulling a sparkplug a squirt a helping of WD40 on each housing. I used WD40 on a motor that sat for ~5 years, rear rotor had a stuck seal. let it set overnight and in the morning I was getting ~10-12 psi higher compression readings and no more stuck seal.

 

haha... didnt even notice...

i picked up some carb cleaner... if it cools down a bit ill go try it out...

 

i would try this one before anything else, it doesnt cost anything and it may very well fix your problem

 

as soon as i can get her started with out flooding out on me, then i will