Hi,

I'm new to RX7club, but I have been a member of the FC3S.org site for a while now. I have some problems with my motor I just rebuilt. I will list what the symptoms are, as well as whats been done to the motor. OK, here goes: First thing, the TPS doesnt want to set, it is set by the lights, yet my idle still hunts around 1500-2000 rpms unless I hold the brake and let the clutch out in gear to "drag" the RPMs down to about 1L, then they will fall to about 500, then come back up. Also, light throttle accel and cruising results in herky, jerky slaming motions, from the outside, it looks like i dont know how to drive a stick. If i give it alot of gas starting and slip the clutch a little, it will drive fine, its only on slow accell and light, to medium throttle accel. whenever I let off the gas, it backfires at least twice on decel. When the car idles, I hit the gas lightly, and i get a few "coughs" and sluggish acceleration. Heavy gas at idle gets coughs and alot of hesitation. Also, the computer wont let me set the timing. I ground the connector, and as soon as i see the timing marks start to move toward the pointer, they jump from retard to advance and the idle revs up and down from about 1K to about 1800 rpms. Ok, heres what the motor has: Fresh rebuild with 600 kilometers on it. New O2 sensor, gutted cat, no air pump or ACV, no EGR valve. Streetported motor. stock injectors, stock boost. Tuned computer. All vacuum lines replaced with silicone. Anyone have any ideas? any help is greatly appreciated, thanks..

Neil
90 infini 3
87 Sport

 

I forgot to mention that I used FD housings in my reuild, and the rear coolant passage doesnt exist on FDs and I removed the coolant factor from my throttle body, however, the "cold start" assist is there. Before I blew the engine, the car always started right up and idled at a steady 800RPms, no matter what. Do I need to removed the thermowax unit? is the Throttle Body mod worth doing? thanks again!

Neil

 

Dont know about the timing, but the jerkiness and idle-hunting (after correctly setting the TPS) is a dead giveaway for a faulty TPS. You cannot adjust it anymore, you have to buy a new one....

 

do not give this guy any help!!! he is the biggest loser on the planet! should never even be allowed to ride in a 7 let alone own one!!!


















just kidding neil
its alf by the way
as for advice change the TPS
put a stock ecu in ad see what it does what computer you have in it now? make absolutly sure you have no vacuum leaks!!! just swap over to the Fd intake and tb and you wont have to worry about the stupid TPS anymore and get rid of the maf sensor!

 

check the CAS also

 

no other input?

 

I have some input, put the damn gun down you are scaring the children =P

 

Yeah man, that **** is pretty ******* scary... freak

 

lol! when i get my car here in tucson i will put the gun down! until then i am one pissed of ************! hence the gun

 

Alf,
calm down man..it'll be ok...Scott is taking good care of your 7 while you're gone. I see it racing all over the place!! just playin..but seriously, how have you been? whens your car getting sent?