jakereed

I think I didn't do my first post right. My name is Jake and I recently finished restoring my RX7 that I've owned for 15 years. She starts and idles just fine. Under lite acceleration their isn't a noticeable problem until you press down on the gas a little further. The best that I can explain is that it hesitates like she is starving for something extra. When I hit the 3800 rpm mark I noticed the secondary's kick in and she seems to feel more stable but not sure. I feel that I am at a loss here to locate the problem so I thought I would post something about the issue. I own another 86 RX7 that runs perfectly fine so I have been swapping components individually to narrow down the issue. Here is what I have done and tried with no luck. If their is anything or thoughts I will try anything. Thanks


New engine, replaced the wiring, swapped throttle bodies, intake, replaced all gaskets, checked all vacuum line individually, ohmed and tested AFM, fuel filter,fuel pump, spark plugs and wires. Ohmed trailing and leading coils, checked timing 20 times, map sensor, fuel injectors, atmospheric pressure sensor, Tried 3 different TPS units nice that these work I hear their expensive, swapped ECU, verified all electrical connections were good, I almost thought it was the 6 port induction so I took that apart and made sure the axillary port valves were in the right spot. Actuators move freely. I also check the ecu for trouble codes and their are none present. replaced fuel regulator as well, all four switching solenoid valves work.

If their is anything you might want me to recheck I will. I'm going crazy on this mystery.

Aaron Cake

iTrader: (1)

Have the injectors ever been cleaned and flow tested?

Have you checked the ECU grounds as per http://www.aaroncake.net/rx-7/grounding.htm ?

jakereed

I took the primaries off the week before last and I could here the solenoids activating when I applied power to them. I won't rule it out because they are from an RX that sat for about 6 years. Originally I suspected the fuel pump as the cause so when I removed the fuel pump from the tank of the parts car I could tell the fuel that was still remaining was turning into a thick sludge. I tried to power the fuel pump in my kitchen but she didn't lite. The fuel pump that I pulled from the car I'm talking about still worked but I wasn't sure if the volume was enough so I bought another one to see and that wasn't the cure. It could very well be that since these primary injectors I pulled from the parts car that one of them is clogged "or both". So I'm taking the advice that I asked for and purchased 2 new fuel injectors tonight to replace the primaries. As for the grounding thanks for the link. I followed this very closely. Its a fresh rebuild and I wanted to make sure I wanted all electrical to be solid. I'll try to post some pics so that you can see for yourself. Thanks

jakereed

New fuel injectors arrived tonight. I'll be installing them tomorrow night. Crossing my fingers in hope it is the cause.

jakereed

I installed the new primary injectors yesterday. Surprisingly when I turned the key the engine didn't die like it normally does when I first start it in the morning. Idle is much better, not bouncing around like it normally does when warming up. Acceleration seem a whole lot better but the hesitation when accelerating is still their. I'm still open for thoughts on what else I can do. Thanks!

satch

iTrader: (1)

Specifically, at what rpm's does the hesitation occur?

jakereed

I would say for all ranges above 1500. If I step on it the car looses all power and tries to grab itself again. By then I already have let off the accelerator. There isn't any backfiring either. Another example is if I'm say in 2nd gear or 3rd. If I keep my foot on the accelerator at a certain speed for a bit the hesitation will go away until I try and accelerate some more.

satch

iTrader: (1)

You want to make sure the TPS is set properly and what fuel pump are you using, stock or aftermarket, NA or turbo?

jakereed

I'm sure its not the adjustment on the TPS. I know this because I went ahead and swapped the entire intake over to my working RX7 and drove it around just fine. So that was pretty much ruled out. I installed a new stock fuel pump about a month ago, and did the same thing with the pump I replaced. I put it in my daily driver and it works just fine. Much of a puzzlement and thanks for asking these question. Same thing done with the AFM, bac valve.

DJ Apex

ya

satch

iTrader: (1)

The TPS would still need to be reset. The Green/Red wire should read 1 volt w/key to on and the engine fully warmed as it can be. After being fully warmed (20 to 30 minutes of driving time) it would take less than two minutes to check the voltage.

jakereed

Thanks for the info Satch! I will check the Green/Red wire for 1 volt when the key is on and the engine warmed up. I'll also check it on the other RX for comparison. I'll let you know tomorrow night. Thanks again!

jakereed

When the throttle isn't pressed I read about 1 ohm. When the throttle is open I read about 5 to 6 ohms. I haven't pulled the battery out about a week ago and thought I would play around a bit. I put the battery back in and pulled the crank angle sensor out and realigned the marks with the timing pulley. Turned the key and she started right up. I let the car idle for about ten minutes and took it down the road. Surprise Surprise their was no hesitation. I drove around for about ten minutes and pulled the car back into the garage and turned it off. About an our later I decided to take it to the store. The second I put my foot on the gas the acceleration issue came back but much worse. I managed to get the car back into the garage and now in neutral the engine revs horribly. Any ideas guys from what is happening before to now?

Aaron Cake

iTrader: (1)

Did you stab the CAS according to the procedure in the FSM?

When was the last time the plugs and wires were changed?

I hope you mean 1K and 5/6K, not ohms. Remember that when the TPS is adjusted, the car must be fully warm for the cold start cam to disengage.

jakereed

According to the book yes. The plugs and wires are new. Yes that was 1k and 5/k set after warm up. I matched the values to my other 86 as well as swapped the entire upper assembly including the TPS to my other RX7 and it runs perfectly fine. So I'm 100 percent sure its not the TPS. Puzzled

jakereed

https://www.rx7club.com/members/jakereed-69653-albums-she-stands-currently-i-give-myself-credit-painting-myself-5331/

Just a couple of photos.

cheecho28

hey did u ever fix ur problem I'm haven the same issue....pls help me

lduley

iTrader: (1)

Thread is 2 years old, please start own thread

misterstyx69

iTrader: (142)

thread is 2 years old.
poster has not been ON for 2 years.
Thread info is Retained but this OLD thread is now Closed so the "New guy" can post his OWN Thread as he rightfully should.
you gotta learn to fly..