chrisw80

iTrader: (8)

Hi


thanks for reading this. I have an 87 t2 rx7 with a new j-spec engine installed and im so frustrated with it because its bin like 2 years and I've tryed everything to get my car to idle. and i do have good compression (new engine) only 200 miles on new engine.

ok heres the problem i can start the car and i have to keep my foot on the gas or the car will stall out / turn off / the engine will just die on me. and it will not idle at all no mater what i do and I've driven it like this a few times and i get really bad gas mileage on it. I have more miles on the back of a tow truck than i do driving it. I've already checked for vacuum leaks in fact I've replaced every vacuum hose on there 3x's already I've replace the lower intake mainifold uper intake mainifold did the throttle body mod, disconnected 2endary injectors to see if there staying on for some reason but i plugged them back in because thats not it I've tryed every trick in the book. and i can dissconect the bac plug on the side of the mainifold and it makes not differance. Ive replaced the entire wiring harness. changed out ecus with several different ones including the same moddle but a different one.
dose anyone have any idas at all? the car will not idle i can rev the car up and down just fine and with my foot on the gas and i can drive it but there is no idle at all even when i screw in the idle stop screw to try and hold the idle up i can get it to go blow 15k - 1k rmps the lowest ive ever bin able to hold the throttle open was 1k but that only lasted for like 1min at the most. dose anyone at all have any idas ive read most of the fsm online and have tryed everyting and nothing has worked ive also searched the entire rx7 club data base and nothing. if anyone has any possable idas on what this could be please let me know. thanks

RotaryResurrection

iTrader: (8)

Does it seem really, really low on power as well?

Sounds like it's only running on one rotor to me. That can happen because of an ignition, fuel, or compression issue.

You say it is a jspec engine, and also a "new" engine. I assume that means a "new to me" used jspec engine. As with any used/junkyard/jspec engine, I have seen them arrive blown, or blow shortly after being put into service. Rotaries that sit for extended periods of time can lose compression during their sit, or shortly after being reinstalled. I encourage you to repeat your compression test. www.rotaryresurrection.com ---> tech ---> compression check

Next check to be sure you have spark on all wires, and that all are hooked up properly. Use a known good or new plug for this test...lay the wire with plug in it beside a ground and have someone crank the engine. Look for a blue/white spark. Stock plugs foul easily so you may want to change them to be sure that is not the issue...a fouled plug can lead to a rotor not firing.

You could have a wiring, ecu, or injector issue that is only firing one primary injector. This is a bit more complex to diagnose. You'll need to remove your upper manifold to get to the lower injector rail. UNbolt teh rail with wiring and injectors intact...lay it sideways so you can observe the bottom of the fuel injectors. Use spare wire to hold the injectors to the rail while pressurized by snaking the wire over and under in an X pattern. Have someone crank the car while you observe the injector output. They should both fire equally one after the other. If one does not fire, take that one out of the rail and bench test it with a spare injector plug (or 2 small clips) and 12volts directly to the terminals. IT should click, and you should be able to blow through it with compressed air when open. IF it does not open, the injector is bad. If it does, check your electrical signal to the injector. You should have +12vdc on one pin of the plug anytime the key is on; you should get ground trigger when cranking the car. use a noid lite to inspect the trigger signal, you can get it at autozone for 5 bucks. Lack of trigger signal on one injector but present in others indicates a wiring or ecu issue.

You WILL find your issue following those steps exactly.

chrisw80

iTrader: (8)

results


Compression: feels really strong and very smooth. dosent seem like its slugesh or anything well driving and when the 1st engine blew it smoked really bad this one dosent really smoke just a few senconds on start up.


spark:

very very weak spark. (compaired to a differnt rx7 that my friend has) it seems that the coils w/ igniters are geting 12v to them and there brand new plug wires and plugs. however ive had to install like differnt plugs several times because when i pull them there full of fuel big time mainly the bottem 2. these rx7 plugs are expencive compaired the reg plugs i think it was like 6 bucks a plug at shucks. if i upgraded to a msd box would i get stronger spark?

fuel

im still working on this one? you say its called a (noid lite) ? and i just had the injectors cleaned and tested by a shop but im going to retest them useing your method i want to rule all the problems out.also ive oreder new injector seal fit because i dont want to reuse the same seals from what im told. and there 550cc high impedance injecoters stock. when the swap was done the car was set up to use low impedance so the guy who installed my engine for me had to bypass the resistor block to run the high impedance well thats what he told me? also when i was trying to drive the car i get really really bad gass mileage like it dumps fuel i think it was geting like 40 miles to the tank of gas and you could smell it was running super ritch mixture. also if it makes a differance i only put like 92 octane gas in it premium.

thanks agin for the help on this. what should my next step be?

3RotorRocket

Any popping from the exhaust?Could be a bad afm.

chrisw80

iTrader: (8)

ive replaced the air flow meter 2-3 times and its made no differance but if the afm's not pluged in it makes a big differance. how can i test the afm bit im prity shure its not that and its working good.

OneRotor

iTrader: (3)

you said that your plugs are always full of fuel, this indicates that your motor is flooding out, which is probably being caused by your weak spark because you said you had your injectors cleaned and flow tested. Your coils and ignitors may be getting 12V, but are they able to use the power that they're getting? Replace your coils and ignitors. This should fix your idle issue and make your car run cleaner and smoother.

chrisw80

iTrader: (8)

well its one of the only things i haven't replaced and i dont think its going to make any differance ive herd that the coils w/ igniters never go bad. but im out of idas so ill replace them.

RotaryResurrection

iTrader: (8)

Nice to see that exactly none of my test procedures were followed or reported on. Guess you can lead a horse to water but cannot make it drink.

chrisw80

iTrader: (8)

what are you talking about i did follow your test steps im still just working on the fuel one

Does it seem really, really low on power as well? (No seems ok)

Sounds like it's only running on one rotor to me. That can happen because of an ignition, fuel, or compression issue.

You say it is a jspec engine, and also a "new" engine. I assume that means a "new to me" used jspec engine. As with any used/junkyard/jspec engine, I have seen them arrive blown, or blow shortly after being put into service. Rotaries that sit for extended periods of time can lose compression during their sit, or shortly after being reinstalled. I encourage you to repeat your compression test. www.rotaryresurrection.com ---> tech ---> compression check (dont have compression gauge but i pulled the plugs and it feels nice and strong)

Next check to be sure you have spark on all wires(did this and yes they do but its weak), and that all are hooked up properly(yes they are). Use a known good or new plug for this test...lay the wire with plug in it beside a ground and have someone crank the engine. Look for a blue/white spark(so weak i cant tell the color of the spark). Stock plugs foul easily so you may want to change them to be sure that is not the issue...a fouled plug can lead to a rotor not firing. (i cleaned up the plugs and reinstalled them)

You could have a wiring, ecu, or injector issue that is only firing one primary injector.(still working on this one) This is a bit more complex to diagnose. You'll need to remove your upper manifold to get to the lower injector rail. UNbolt teh rail with wiring and injectors intact...lay it sideways so you can observe the bottom of the fuel injectors. Use spare wire to hold the injectors to the rail while pressurized by snaking the wire over and under in an X pattern. Have someone crank the car while you observe the injector output. (working on it well we speak)They should both fire equally one after the other. If one does not fire, take that one out of the rail and bench test it with a spare injector plug (or 2 small clips) and 12volts directly to the terminals. IT should click, and you should be able to blow through it with compressed air when open. IF it does not open, the injector is bad. If it does, check your electrical signal to the injector. You should have +12vdc on one pin of the plug anytime the key is on; you should get ground trigger when cranking the car. use a noid lite to inspect the trigger signal, you can get it at autozone for 5 bucks (autozone is closed today have to get it in the morning). Lack of trigger signal on one injector but present in others indicates a wiring or ecu issue.

You WILL find your issue following those steps exactly. how did i not follow this and also the www.rotaryresurrection.com website is down i think or my pc cant acces it one of the 2. thanks

newbieRX-7

This is the exact thing that is happening to my 88 RX-7 bur im losing power also.
Zac

package

for what it's worth had the same problem when I repaced the motor on my 1991 RX7 repalced the o rings and it's running like new

chrisw80

iTrader: (8)

what o-rings are you talking about where are they located and what do they seal etc need info. thanks

chrisw80

iTrader: (8)

Also just found out that when i start my car up and its cold out you can see the exhust coming out in the engine compartment it looks like i have a big exhust leak could this effect idle?

Gargoyle

Any luck fixing your problem yet, Chris?

My '87 has started flooding very easily the last couple of days, and it has a rough idle. In fact, it's rough no matter what RPM it's at. As it warms up, it gets smoother above 2000 rpm, but still rough below that. It hasn't died on me yet, but it's come close. It seems to flood every time I park it, and I find myself removing the injector fuse to purge out excess fuel way too often.

Anyway, I plan on following the advice people have given above, and I'll report back. Everything RotaryRessurection said is backed up by my Haynes manual, so I just need to test some the stuff out before it gets worse. Getting too cold to walk to work.

CoRDiTe

I had this problem with my FC two of them. One was the Intake had the vaccume leak. I kept checking all the hoses and replacing them and nothing fixed it. The screws that connects to the Dynamic Chambers were loose and allowing a Leak. The other problem I had was the injectors were just bad. even cleaning them didn't do the trick. Cleaning them doesn't mean they are going to work again. You might be better of dynoing the car or running some codes to see what the problem is instead of playing the Guessing game and wasting so much money trying to figure out what the problem is. Another problem I had was I could smell my Gas being mixxed with my oil. (this prob. was on a differnt FC motor though not the same one) and later on it lost the compression and I was blowing all my coolant through the exhaust and the motor died. It still runs but had no compression whatsoever. took me like 15-20 min to get it started. Maybe that could help you out. Check your oil and see if you smell gas in it, and when you start your FC check the back to see if you are blowing out water. if you are, Prepare for another swap or rebuild.

chrisw80

iTrader: (8)

bump^ im out of idas. i have tested and replaced everything. anyone have anyother ida's as what could be wrong with my car? thanks

FB II

well, if you could i would seriously try replacing your coil packs. if anything, swap out with one of your friends fc for a minute just to test.... because they DO go bad. no doubt about it. just not as often as you are led to believe.