After my stock fuel pump crapped out, a brand new TT supra pump went right in. Upon the initial couple of miles, everything was good.

Now today i go attend a mini meet between me and a couple of my friends, before the actual meet, i do about 45 minutes of city driving (cause they want to go to a car wash etc etc) so car is def warmed up by now, plus the ambient temp is about 67 degrees.

Anyway, i noticed that my car will jerk or choke during 2nd and 3rd gears in the low revs, meaning if i ease the gas, it will be ok, if i get on it (not wot), then the car jerks a bit or hesitates, then picks up. Off the line, sometimes it will even stall out!!! Like when you're clutching out, the revs would drop and sometimes the car will die. It even died when i shifted from 2nd to 3rd and gave it gas, the car just died. Im not sure if this is a fuel related problem although i assume it is cause that was my last mod i done. Theres gas in the tank (about 1/4 or slightly above 1/4). Do you think the Supra pump is too much cause im still on the stock ecu?? Maybe its choking the engine at times??

I then noticed on my limp home that at stop lights, i would hear some ticking coming from the engine bay or clicking. Its not loud but i could hear it from inside the car and i have a loud exhaust. My vacuum shows 19-20 at idle (at 1200rpm), with the fans on, yes i know its high but do you think possible theres a leak??

Any help would be greatful. Thanks

Rob

 

the clicking could be spark arcing to ground from a loose wire, bad coil etc..

the pump should have no bearing on fuel pressure at all as it will not overrun the regulator. especially at idle when it only sees ~8v if your wiring is stock

 

Ill check my plug wires to see if they are tight. Coils are supposedly "low mileage", i changed them a month ago.

Ok so now that its not the pump, what else fuel related could it be??

Now im thinking something along the lines of a switch or a connection thats loose cause the problem is intermittent. My idle is fine if im in neutral. Sometimes when im coming off 1st gear when clutching out it would stall out. Sometimes when i shift from 1st to 2nd or 2nd to 3rd and get on the gas it will either jerk or car will shut off even if im already moving.

Theres a bad connection somewhere thats shutting off the pump at times maybe?? What about the fuel pump resistor, should i check that?? or how bout the relay??

 

Well plug wires are on tight.

Could it be a TPS or an ISC problem?? Or maybe something to do with the TB cause the TB mod was done.

 

Check all your switches, especially the clutch switch.
Here's a great way to do it:

https://www.rx7club.com/showthread.p...+clutch+switch

TPS would be my next guess.

Good luck

 

Maybe a clogged fuel filter. The pump could have had some trash in from sitting that was cought in the fuel filter. Def sounds like a fuel related problem. I would do like you have already mentioned and check all connections.

 

Well fuel filter is brand new, oem just put in 2 weeks ago.

But i tried pinpointing this problem today. I checked all visible connections, vacuum lines etc and everything seemed to be ok. I did notice that the first 10-20 minutes of driving, everything is fine. The problem occurs and worsens when the car is fully warmed up and since now its spring time (about 71 degrees out now), i would imagine it has something to do with heat.

So now i know problem occurs when engine is hot or at full temp. What sensor or connection has this problem when car is hot??

I will check the clutch switch or other switches but i doubt its this now that i know problem occurs when car has been running for a while.

 

Could the fuel relay be stuck in low speed/ low voltage mode? The clicking you hear could be it trying, repeatedly, to stay in full votage/ high speed mode. Hence why it runs normal when cold and not when fully warmed up.

I don't know, just sending out ideas.

Godd Luck,
Joe

Oops, I just read this:
yes, check both. Make sure you have constant bat/alt voltage at the pump.

 

Hmm damn, alot to think about. What about the EGI relay?? i checked it and the plastic casing, the black plastic casing was cracked. I guess someone used a pair of channel locks to take it out and broke the plastic casing. It still works, i checked but do you think maybe it still could be faulty??

Keep the ideas coming guys, i appreciate it.

Rob

 

washed you car then this started happening?!?! could water have gotten into that crack and start shorting the relay?

there is a fuel pump (speed) relay in the front fuse block as well...9V -> 12V relay.

check the fuel pump resisitor under the master cylinder.


how do you know you old pump died? could it have been a fuel pressure regulator issue?

 

Nah it def had nothing to do with water.

I kinda did straight assumption about saying its the fuel pump being the initial problem to my car because last time i had symptoms like this (back when i had my talon), it was the fuel pump. And since i replaced nearly everything on the FD before the fuel pump and it still wouldnt start, i had to get a fuel pump.

But now since everything is nearly brand new or brand new. Ignitor, coils, plugss, plug wires, fuel filter and fuel pump, i dont see anything besides the obvious that could be wrong. Something is shorting out or has being disturbed when its being heated. When i drive the car for first 10-20 minutes, everything is perfectly normal. Car starts to get hot, then it acts funny and worsens if i continue to drive.

The day i made this thread, the car stalled randomly (more times off 1st gear) about 5-6 times before i got home (which was only 15 blocks away). Something is triggering something to where its stalling out or maybe shutting off the fuel pump (it seems??) when the car is hot. When car is cold or just warming up, no problem, its def heat related.

Thanks for the advice, ill continue to inspect but please give more insight. Thanks.

 

Another forum member pointed out to me that maybe because im on the stock ecu? Could that be a possible cause to the problem as well?

Cause i am still on the stock ecu, im gonna try to reset it and see what happens. I doubt anything will change but never know.

 

how was the small rubber hose that connects the pump to the metal hard line?

 

You mean at the top of the assembly tree itself??

Im gonna go and double check to see if anything seems out of the ordinary.

 

Update on my little problem.

I found out, well sorta because im an idiot and i like to assume alot instead of actually knowing lol that its my tps.


Too many incidents and "little things" made me come to the conclusion that it is and im 99% sure it is.

First off, i bought a polished UIM/TB with unknown miles, and the TB came with the TPS. THEN i notice that at startup, idle is confused. Its not crazy like jumping up and down or idling too high or about to die but its flucuating from like 1200-1300. And even after car is warmed up, idle is the same which still hunts and never is at steady rpm.

Car drives fine when cold but when car is warmed up, idle wants to give out when shifting (you know when you clutch in, the revs drop. Well the revs sometimes want to drop so much, it actually stalls between shifts or coming out of first gear).

So im pretty sure its the TPS now. I know i can just adjust it but with unknown miles of this thing, im just gonna go ahead and try to get a low mileage one. I dont want to go crazy testing this one and adjust it etc etc.

My question is do i have to adjust the new one i get? Or can i just take old one out and put new one in? And do i still have to warm up the car first before i take the old one out, even if im not adjusting it???

Thanks

 

Bring me the car I'll sort it out. There is a whole adjustment procedure for the tps

 

I know, i didnt forget about you, just trying to see if i can do this on my own. At least we can eliminate this as a possible factor in the problem.

 

try replacing the fuel pump resistor relay thats what code i pulled on my ecu check your codes also..