Slade Gunar

the title says it all. its magic.

the car ran like a champ for months. started up beautiful, idled perfect at 750. my step brother tried to move it, got it down the driveway (clutch in engine wasnt engaged) started going back up and it just cut out. now the car wont run for more than 3 seconds before killing itself. when you start it revs up to about 2200 then kills itself. air pump, emissions gear, fast idle, subzero start and all that nonsense is still on the car

now this is a 87 na 5speed. the engine was rebuilt a few years before i bought it. so far this is what has been done to this car:
obviously first tried checking fuses and deflooding. which it wasnt
rewired the fuel pump and replaced with a spare t2 pump and new filter
cleaned and checked the maf and the k&n drop in put clamps on the bac hoses and cleaned the bac valve.
double checked the tps with a multimeter
checked all over the place for vac leaks havent found any so far and replaced numerous hoses.
checked both leading and trailing for spark
checked the grounds, added additional strap for testing
replaced the tumbler with known working unit
pulled and re soldered the cpu and main relay... *ive done it on hondas before--was getting desperate at this point*
previous owner was a goofball and cut up the relays above the pedals and had them all crimped together so i re soldered all the connections. i think he was trying to install a alarm or possibly a fuel pump kill switch but instead just made a mess of things.

it was either cursed by a mongolian banana wizzurd who is offended by my swanky blue interior or its just a piece of ****. im thinking more the latter.

could this be related to a fpr, bad cas, or even a failed ecu?i have a video of what it does exactly if anyone thinks it will help

i really hate having to ask for help with this but it has me completely baffled. been through numerous threads and cant get this pinned down. only thing i can think is that my brother keeps his feet really high on the pedals and he maybe knocked one of the crimps and it shorted something out. cause it ran perfect before he tried to move it.

any help or advice would be appreciated

satch

iTrader: (1)

Try jumpering the fuel check connector.

Slade Gunar

that was the first thing i tried after checking the fuses and trying to deflood the engine. oddly enough jumpering the connector didnt do anything. after that i did the fuel pump relay mod and tested it with the pump direct to the battery still did the same thing going out to check the fuel pressure again today and test the fpr

satch

iTrader: (1)

One of the wires that are the part of the fuel check connector might be bad. The Brown wire would have battery voltage w/key to on and the Black wire should have a ground on it w/key to on. It is imperative that the Black wire has a ground on it or the car won't run w/key to on. The Black wire provides a ground to the AFM which then passes the ground on to the Brown wire which then creates a ground at the Circuit Opening Relay. Also, the Circuit Opening Relay found to the right of the steering column and is Yellow and Black w/five wires "must" have voltage w/key to on at the Black/White wire located on the top row middle wire. No voltage w/key to on and the car will die quickly upon start up.

Slade Gunar

this is a idea of what the wiring inside the car looked like when i got it.



this is the relay your talking about right the one with all the crimps on it. the pump kicked on with the test connector after i fixed that mess figured there was a short in there somewhere. i checked the wires voltage based off of your last post and everything checked out. however.... the plug that is just hanging without any crimps does not have a relay or anything plugged into it. i know in my grey car there is a relay plugged into it but my grey car is also a automatic so i am not sure if that makes a difference.

Slade Gunar

that is exactly what it does. i had been messing arround for awhile so the charge pack was going dead and the battery isnt the best either.

Slade Gunar

oh also i hooked up a gauge after the fuel filter and engaged the pump it read 30psi i hooked a vac pump up to the fpr and at -25 vacuum it read around 18-20 psi. it seems alot lower than it should be though i know my grey car reads 38 and it takes almost a day for the fuel pressure to fall to 0 this falls within about 10 minutes back to 0.

satch

iTrader: (1)

Clear pic of the Circuit Opening Relay

https://www.rx7club.com/showthread.p...epotato&page=7

Wire in the top row far left passes voltage on to the Blue wire which powers the pump when starting the car. Once the rpm rises above 500 the Blue pump wire receives voltage from the top row center wire. Thus there are two relays in the relay for one is responsible for starting and the other is for running the car. Since your car starts up, the relay responsible for starting is obviously working. You stated that when the fuel check connector is jumpered and key to on that the pump works. If that were the case then the second relay must be working as well. Now are you sure the AFM flapper door is not stuck or does it open fairly freely? You might want to disconnect the AFM with the fuel check connector jumpered and try to start the car. And since you believe you ironed out some of the wiring at the relay have you tried to start the car w/the check connector jumpered or not?

EDIT: And the turbo fuel pump might be a bit too much for the NA.

Slade Gunar

~~~Post#6 is a video btw~~~

im positive the maf door is operating. i cleaned the maf and tested it on my other rx7. that last video was with the jumper on the test connector. i had been trying it with the jumper on and off and with the pump wired directly to the battery

satch

iTrader: (1)

Have you also checked the Main Relay to see if it is staying closed w/key to on after trying to start the car. If it were the Black/Yellow wire at the leading coil and the Black/White wire at the four wire Green check connector located near the leading coil would have battery voltage on it.

Perhaps other things to look at are the Pulsation Damper, FPR and pins 3E and 3C should have battery voltage w/key to on as this verifies if the injector plugs are properly seated w/the injector. And if the wiring to the AFM was problematic then taking an AFM from another car will not help and this is why one thing you should do is unplug the AFM and try to start the car w/the check connector jumpered. The AFM might be creating problems w/the Vref voltage. If this were okay then the Brown wire at the TPS or Pressure Sensor would be 5 volts w/key to on. If it were much lower then something is pulling it down.

Slade Gunar

the main relay next to the clutch cylinder? i had that out of the car and resoldered all the points on it and tested that on my grey car as well. i only resoldered it because i had main relay hot start issues with my accord which was doing the exact same thing. i was getting desperate at that point. i have open/closed loop and diagnostic leds wired in the 4 wire check connector next to the leading coil as well which are inside the cab to see if its throwing a code so i know there is voltage going to it.

Slade Gunar

im back at my house tonight so i cant test anything until tommrow. i will try unplugging the afm and jumpering the check connector to see if it will start and stay running also ill test the voltage at the tps brown wire.

as far as the pulsation dampener i honestly have no clue on its condition and the fpr i think is working correctly. i have a rail adapter and a cheapo ebay one laying arround so i might throw that on to see if itll work. im also debating on draining the gas and putting fresh in as well. ive honestly reached the point with this car that if its not running again soon im just going to junk it.

Slade Gunar

alright the other day i pulled the 2ndary injectors out took them to my homemade injector cleaner setup and cleaned both. i couldnt get the seals at any local parts store which im not suprized so i ended up using some 10mm-3/8 hose to seat the injectors in the manifold as a temporary fix while the proper seals are on the way.

first thing i tried was to start it again with the check connector jumpered. it did the same thing as before ran for a few seconds then stalled and fuel pressure was at 0.

2nd try again with the check connector in and the fpr vac line disconnected same stall but held 30psi in the line.

3rd try check connector in, afm disconnected. fpr reconnected. same situation as before ran for a second then stalled but threw a afm code on the reader pressure to 0.

4th try unhooked the jumper hooked everything back up as it should be. started the car and waited for it to catch and i hit the throttle to about 1/4 car started to run high arround 3-4k took foot off gradually tps read 52% afl at 5.4% got it down to roughly 2700 before it popped and stalled out at 32% tps. car threw a tps code after the stall.

i didnt see any brown wires on the tps or on the 3pin harness so i wasnt sure which one to test. ill take a spare tps over tommrow and try it again as well as drain the gas out of it when theres daylight.

Slade Gunar

Alright, heres a update on this if anyone actually had been through this or was using it for troubleshooting and whatnot. This is going back more than a few weeks so bear with me here, i've been busy getting other cars ready for atco.

My next step was to drain out all the old gas from the car and heres what i came up with i put some fresh 87 in with 5w30 in because i couldnt tell if that was premixed (probably not judging from the last owner) or if it was just god awful old gas from colorado over 2 years ago.

I got it running at that point, but something still wasnt right with how it was idling and wouldnt hold a idle without a slight ammount of pedal and air bypass/ throttle plate stop screw adjustments werent helping. Something was still wrong and i had decided to pull the tb off and inspect. After the tb had been pulled i decided to go ahead with this
After it was pulled and on the bench i had noticed the vacuum ports on the side of the plastic aws thinger--technical term there, were cracked and broken which is why i decided to go the route of the tb mod and the fact the cat is hollow so its unessicary. After all was said and done the car idles arround 800. For now at least.......