Wringley

I just bought an 1993 Rx7 and sometimes after driving it I would stop at a 7-Eleven and i would Turn off the engine. i would then try to start my car up again but it wont start. I noticed that my Overheat Exhaust System Light would be lit. I'm assuming that is because of some overheating issue? cause after like 20 min it would start up again. Im a newb at this so im just wondering if theres something wrong with the engine.

Aaron Cake

iTrader: (1)

It is very unusual that the exhaust warning light is on. I am not an FD guy, but the FCs have a similar system (as do the 1st gens). It's just a temp switch on the floor above the cat that will trigger if something very bad is happening (ie. car is on fire).

When does it light up? When you tried to start the car, what happened? Describe the problem exactly.

dgeesaman

iTrader: (7)

Does the car have a PFC ECU? If so, the exhaust warning light actually operates as the signal for an electrical fault.

http://www.clubrx.org/media/pfc/pfcwarn.pdf

David

blown_apex

How many Miles on it? Could be the Cat clogged? Just a thought

Captain_Panic

iTrader: (15)

Hmmm... if the Cat was clogged that badly you would think the car would have problems prior to shutting it down. The Cat shouldn't continue to heat while the car is off.

I am with Dgeesman here. I think this might be something electrical that gets fouled up when the car gets HOT. PFC will react that way.

Wringley

@Aaron Cake: Well usually after I drive i let the car sit for like 4-5 min since I don't have a turbo timer. But sometimes when I try to start the car it just wont start. I heard there were some heating problems with the FD so I'm wondering if it had to do something with heat. since i noticed my Heat exhaust light on which I don't see lit very often. when I put in key and try to start the car all i hear is a fan running or something and the engine wouldn't start. I dont really know how to explain it.

@degeesaman: I dont have a pfc. my car is comepletely stock and sadly an automatic. So im no sure if it is an electrical thing. but it might since when i got it from the previous owner there are some minor electrical problems.

@blown_apex: it has 98k on the body and 45k on the engine. i dont know if the cat was replaced when the engine was replaced. but it might be a possibility

@dfoster154: Like i said i dont have a pfc but it might be electrical since there are some minor problems. it might be the cat cause it usually happens when the car is off for only 20-30min at a time.

Thanks for all your help. I'll look into the cat as well as the electrical.
if there are any other ideas please let me know. sorry for being a noob :P

dgeesaman

iTrader: (7)

No PFC, then it's the actual exhaust overheat sensor.

I recommend you buy a downpipe and when they're installing it, make sure the main cat is also in good condition.

Dave

Aaron Cake

iTrader: (1)

There's no reason to let it idle for 4-5 minutes unless you were driving it hard.

So the engine doesn't even spin when you try to start it, only the fans operate?

If it tends to overheat when sitting still, make sure both cooling fans are operating.

linnadawg

iTrader: (14)

Sometimes the overheat exhaust light comes on when you turn the key forward. Mine comes on randomly but never stays on when the car is started. If its not cranking over check your voltage out at the starter. use a remote starter switch to see if you can get it to crank when its warm while it wont work with the key. then you can isolate it to the wiring. If your car is clicking once then your having a voltage drop out to the starter most likely

drifting in drifting

iTrader: (11)

sounds like a heat soaked starter to me

Wringley

@dgeesaman : aite for sure ill look into it. quick question is it better to fabricate a downpipe? or buy one already made. and what is your opinion on ebay downpipes?

@Aaron Cake : Thanks ill look into it for sure!

@linnadawg : aite ill keep that in mind if the downpipe doesnt work.

@drifting in drifting : like above, ill keep that in mind if the downpipe doesnt work

Thanks for everyones input!

dgeesaman

iTrader: (7)

Definitely buy one already made. There are used ones from good name brands on the classifieds every day for very good prices. Bonez, Pettit, PFS, HKS, etc for $100, can't beat that with a stick.

Ebay parts are a crapshoot. There were a bunch going around a few years back that were made with the wrong spacing between the bolts at the cat end. After enough people bitched they then made midpipes with the same wrong bolt spacing and sold them as a combo. Downpipe + midpipe = boost control disaster for most setups. Needless to say, with the name brands being so cheap on the used market I see no reason to mess with off-brand garbage.

Dave

linnadawg

iTrader: (14)

Dont buy ebay ****. Dont hollow out your precat. I was low on cash so i had to drive around to 20 shops just to get someone to do it. cost me a 100$ at the end. waste of money when you can buy performance. the catalyst inside is insanely hard and cannot be removed unless you cut the main section of the precat. then you have to weld it. when mine failed and clogged it was glowing orange at idle and smoking in the car through the shifter

blown_apex

More of an fc guy. just giving some possibilities

jasonn

iTrader: (10)

What is the usual recommended dp size for the FD?

Wringley

aite no ebay or fabrication :P
Thanks alot guys!