Full exhaust - car wont start!!
 

I just got done installing a full 3" downpipe, midpipe, and hks carbon ti catback. i did have to remove alot of my stock airbox system to get to the downpipe bolts. although its not the first time ive removed and reinstalled the factory air box so i know how to put it back together.

everything seems right. what would cause my car not to start for just installing a full exhaust? would the air pump play a roll? or what about the o2 sensor? its pugged in but maybe got damaged? i cant think of anything that would cause my rx7 not to start.

please help me!!

hope you have fuel for that...


air pump has a secondary air injection into the LIM thru the ACV...never heard a car not start, but lumpy idles.

O2 sensor won't cause the car not to start

when you remove the intake on these cars theres nothing you can really mess up with the car not starting (no AFM) so , as for the o2 sensor, I don't run one at all so obviously thats not your problem

Exactly, since its not afm theres no reason why it shouldnt start. and i knew o2 sensors shouldnt stop your car from starting... but i just wanted to make sure. this is my first fd.

are these cars more tempermental with larger exahaust? maybe easier to flood during start up without the cats and bigger pipes? im going to check my spark plugs to make sure they arent gunked up next.

Larger exhaust should also have no effect on starting. Exhaust restriction only affects stuff at higher loads and RPM's when the exhaust flow is high.

Did you by any chance knock something loose that would affect the starting fuel mixture (like a vacuum hose past the throttle body)?

is the car turning over at all? or is nothing happening when you turn the key?

it's not something stupid like you forgot to reconnect the battery or anything right?

There is a ground strap attached to the exhaust pipe about half way back. I don't know if this could cause a no-start situation, but you should have it hooked up anyhow... Bolt the wire down under one of the midpipe-to-catback bolts.... you should find it dangling back there someplace.

Five bucks says he flooded it.

He probably did what I would have done and started the car with the exhaust off to see how loud/nice it sounded, then shut it down with out warming it up.

Good thought to check plugs and go though a deflooding precedure.

Oh yeah... assuming you get the car going... Full exhaust + Intake is a guaranteed blown engine unless you have the proper fueling for that amount of airflow.

What have you done to the car to compensate for the dramatically increased airflow? I'm not trying to be a "know-it-all".... just trying to save you some money :)

I wouldn't say that, I run intake, downpipe, midpipe and exhaust on the stock ECU without any problems. Just have to keep the boost levels under control. I don't have any creep either, which is kinda strange, but who am I to complain.

O2 sensor would not have done anything to it. Since you remove and replaced the air box, I'd check EVERY line around that area to make sure they're connected. I know I've had problems before because of one stupid line that wasn't connected and problems like that.

Also, the starting with no exhaust thing.... i've done that before, and I've started and shut down Rx7s before they warm up. It SHOULDN'T cause flooding, but it could. If you did that, you might want to pull the injector fuse, crank it for a couple seconds (not long) and then reinstall the fuse and crank again.

Also, I wasn't sure how much fuel the stock system could deliver, but I figured it would run out with exhaust and intake.... so I'm glad I read this post, and now I know to make sure that I have plenty o'fuel when I start upgrading mine. :D Good luck with the problem.... hopefully something helped ya!

My car rolls over... almost sounds like it isnt getting much spark. i can smell really rich gas and i've removed and cleaned each one of my spark plugs and installed them in the right order. still no difference. i've checked all my fuses and vacuum lines. there is no reason why it shouldnt start.

And yes, ive reconnected that grounding wire thats on the exhaust.... no i didnt start the car without the exhaust connected. i did everything right. i just dont understand.

If the only thing you did was exhaust, and the only system you modified was the exhaust, then the car will start. The exhaust will make the car run different, but it won't have an effect on starting. The ground cable, I didn't know about, but since you connected that... you can most likely rule out the exhaust.

It sounds like the problem with the car starting is something that was secondary to the installation. You must've disconnected a hose and forgot to hook it up, hooked up hoses to the wrong place (QUITE easy to do with so many hoses), or maybe even forgot an electrical connector if you had to unplug those.

I wish I'd been through this on an FD, because i'm pretty stumped at this point, but I've never done this on an FD and figured it would be about a 1 hr job. Sounds now like i've really gotta watch myself if I'm going to have to take apart other systems to get into the exhaust.

your problem has nothing to do with the exhaust or the intake unless the exhaust or intake is stuffed with a potatoe or something.

But sense you insist hehe :) Take it all off and then put the stock exhaust back on and see if it starts LOL.

Seriously I would first check the fuses, then make sure you're getting fuel pressure when cranking and spark when cranking, then check all the sensors. If that doesn't work call Triple A and have it towed to your nearest rotary specialist.

Good luck :)

was your car flooded? if it keeps flooding check your tps sensor.

Try a brand-new set of plugs.. cleaning used plugs doesn't seem to work sometimes..

heres two ideas i thought of... before i installed my exhaust i had to move my car about 30 feet. i started it up moved it and turned it off so the exhaust wouldnt get too hot to touch. and i didnt disconnect my battery while installing my exhaust either. could either one of those cause a no start problem?

Ive checked every fuse. they are all good. i double checked the whole air box system, everything is hooked up right where it should be.

does anyone want a cheap FD? i dont like making huge payments on my FD that doesnt even start at this point.

You figured it out - starting the car for a few seconds and shutting it off cold is a common cause of flooding problems. Search - there are lots of threads on curing a flooded condition!

did you install pullys or anything that would have you working close to the crank pully?? its just a question because when i installed my intake and removed my air pump and installed pullys i accidently nicked a little silver sensor on the around 3oclock on the crank pully....

everything was put on and i went to test the car wouldnt turn on.... i tought it was flooded did the prosedure and got new plugs and i checked everything like 3 times... gave up and almost cried...

a week later looking deperatly for an answer that didnt include blown motor, i checked and re-checked and seen the crank pully sensor that i nicked ,and seen that little sensor was slightly bent i did some reserech and found out that it was the crank positioning sensor ... now it made sence, thats what sends a signal to the coils and thats what was wrong with it ..paid like 86 $ at autozone and the car started right up .....

then again it could just be flooded and you need new sparkplugs...

Its crazy how that flooded my ar so fast. i've removed and cleaned my plugs and left them out of my engine so it could air out for about 4-5 hours... I mean, how can a fuel injected car get soooo flooded?

I doesnt sound like its getting much spark... maybe because my plugs are too far gunked up? even though i cleaned them really really good before i installed them?

And no i didnt do any pullies...

So did you get it started? *edit* reread a few things and maybe not.

Deflooding:
-Pull all spark plugs
-Pull EGI Fuse and Fuel Pump Relay
-Crank the motor with fues/relay/plugs out for 15 seconds three times each. Make sure you have a good battery.
-Buy new plugs (may not be needed, but helps greatly)
-Install plugs
-Put the EGI fuse and Fuel Relay back in.
-Crank the car over. If it starts don't let it die, or you'll have to do this again.
-Warm it up completely
-If it doesn't start try again.

Or just tow the car in 2nd at about 20mph tell it runs on its own.

Good Luck
Joe

hmm... i've tried that 3 times now... twice with my old plugs and once with brand new plugs... maybe theres a different way? BTW... i cant really pull start my car considering its a auto.

Have you tried a known good battery? It doesn't take too much of a voltage drop to make starting difficult... like a collapsed cell can do it sometimes...

i threw my battery on my charger for a day because it was slowing down. but when i installed it again i didnt deflood it and tried it and it still didnt start. i'm going to put my battery on the charger once again then deflood it with a different battery or a jump starter unit and then install my charged battery and try it again.

but if that doesnt work, does anyone in WA know of any good FD specialist? i'd like to take my FD to someone who has deflooded them more than once.

Pour some ATF fluid in the throttle body, instant compression and bug killer.


how much you want for it?

Tim