gcbutter

Mods:
PowerFC,
Greddy TD0620G kit,
Double Throttle removed,
downpipe, midpipe

Problem: Car idles jumps from 1000 - 1500.

Tried to fix above problem: Adjusted the TPS to correct specs. Used the Thread started by Damian (https://www.rx7club.com/showthread.p...&highlight=tps) as a guide.
I can get the idle to settle down to about 1200, after that, engine shakes and it wants to shut off. I adjusted the screw on the top of the throttle body to calm the jumping down, as well as adjusted the throttle cable. Also I cleaned out the ISC.

Second Problem: The car does not want to go past 3000 rmp without backfiring and sounding horrible.


I recently replaced the UIM, LIM and TB with polished ones from (cantgostraight, A.K.A Jack). I've been trying to trouble shoot this problem for about a week now. I'm thinking about just dropping it off at RotorSportsRacing in North Carolina and have them fix it (last resort).

Recap: Sounds like a V8, white smoke (does not smell like coolant), Backfiring at 3000 rpm or greater, idle is all sorts of messed up. Help if you can...I'm going to check the compression of the motor tonight with a compression gauge (like they did in the Rotary Aviation video) this is just to get a go/no-go on the engine.

Garrick

gcbutter

I ckecked the MAP sensor. It's still good. My PowerFC reads 2.65volts under PIM. Heres the plan: I have all next week to troubleshoot what ever you guys bring up. After that, I'm going to take the car to RotorSportsRacing and have them check it out. So please help out if you can, I don't want to pay anyody else to fix my hopefully small problem.

Garrick

gcbutter

Bump for the morning people...

BlueTII

How much vacuum does the PFC say that it is pulling at idle? and when it is not running? Make sure that the hose to the map sensor is connected to the vacuum nipple in fron of the TPS, not to the post that is sticking out of the TB above the TPS.

gcbutter

Q: How much vacuum does the PFC say that it is pulling at idle?

A: 219-220 vacuum.

Q: and when it is not running (vacuum)?

A: it says +0.38...weird! It thinks it's getting boost when the car is not even on. BlueTII what does this mean?

Q: Make sure that the hose to the map sensor is connected to the vacuum nipple in fron of the TPS, not to the post that is sticking out of the TB above the TPS.

A: I have it hook up to the nipple below the Douuble Throttle on the UIM,
Pics below.

BlueTII

I do not see a block off plate where the double throttle was removed, do you have something filling the hole? Your vacuum is very weak, -220 @ 1000 rpm is about 200 less then it should be.

gcbutter

It's that weld stuff. The previous owner of the UIM put it in there without issue. I odered a block off plate that should arrive next week.

I did the compression test today with a piston engine gauge. I got 125 psi with pressure on both rotors. without pressure (neddle bouncing method) It was only bouncing from 0 - 50 on both rotors. This would indicate that I'm not getting good compression on both of my rotors. I just don't trust these readings however. When I did the poor man's method (take out the leading plug and feel your finger get pushed away three times, and listen for the air) It seemed to indicate good compression. I'm taking the car by Mazda on moday to get a rotary compression gauge in there to check it out. Can you believe it's $110.00 to check the compression; WOW! I will keep this thread and people posted.

Oh, I just wanted to Thank: Jason (rx7Store), Brian (RotorSportsRacing), and Steve Osley (North Carolina Rotary guru). So far they have been a great help in this process.

BlueTII

Did you change your map sensor setting from "normal" to one of the others? Unless or course you have a GM or Apexi map sensor.

gcbutter

^^

No I did not change the Map Sensor setting on the PFC. I will check however to verify it. Also Thanks alot for your Trouble-shooting help "BlueTII"!!!

bajaman

Have you checked for any engine codes? One of your problems (the no power, 3K issue) sounds like my car when it was stuck in low-pressure fuel pump mode. See if you get a Code 51 when you ground the 10 pin and turn the ignition to 'on'.

rx7what

iTrader: (6)

^ He is running a power FC so there are no engine codes to get. It sounds like you either have a vac leak or a bad map sensor or some time is hooked up wrong. What did you do to your car just before it started acting like this? What mods I mean, or what did you take off and replace.

DaleClark

iTrader: (55)

Typically an unexplained high idle is a post-throttle body vacuum leak. With a large enough vacuum leak, the MAP sensor will have an improper reading, which makes the car run terribly. Double-check everything - any air leak can cause the problem. Make sure you didn't catch something between the upper and lower intake manifold (like the ECU ground ring terminal).

It's gonna be something simple when you find it.

Dale

gcbutter

A: Nothing; well I did change the plugs to all NGK 9's, and put on some Magnecor wires (5-6 months before the problem). I drove to work (no boost), and just before I shut it off, it stalled. Then Voila, my current problems... The car has been running great until then.

To answer the MAP (PFC setting); I went out to double check it. It's set at
"option 1". I know I have never messed with this setting at all, so I guess the car has always been set at that. I will check the PFC sectionof the forum to see what the diffrence is between option 1-3, and the normal setting.

Monday I'm going to Mazda to get the Compression numbers, I will post the results.

ecarver2

any word yet?

gcbutter

^^ No word yet! I have had the worst luck.

First: Mazda was going to check the compression of my engine with a piston gauge, and not a rotary one. They wanted to charge me $110.00 for that, Horrible!!!

Second: I was just going to take the car up to Steve Osley in North Carolina. Well I borrowed my friends truck and rented a car trailer from U-haul. Well when we went to load the vehicle on the trailer, the trailer popped off the hitch and messed up his tail-gate. There went that idea. Took the trailer back to U-haul and they are going to repair my friends truck. It's just another bump in the road. Hopefully I will be able to make it to North Carolina this up coming weekend. (oh just in case you wanted to know; U-haul hooked up the trailer to my friends truck, Horrible!!!)

I'll keep everyone posted.

CantGoStraight

Garrick,
Was the car running ok before the polished parts were put on ? ? ? I know it's a pain but have you tried putting your old parts back on one at a time to see if anything improves or changes. Jack

gcbutter

^^

Jack,

No, the problem started before I put on the polished parts. It actually started the day I recieved them in the mail. I will be sending you the UIM Tuesday. I will be sending the LIM, TB once the problem is solved. Thanks Alot for all your patience...

Garrick

rotaryrevolution

yah im having the same exact problem you are, unfortunately i cant help you...if i some how get mine working ill let you know, untill then i guess were both screwed.... im confused about how this happened..... ran perfect during the day, later at night it started doing what it does now just like that....... i just got it back from having an electric air pump put on to pass emisions, drove it for some time, put new plugs in (also NGK9s by the way), as for what i have done, stock engine, power fc, non sequential turbos, greddy profecb2 boost control, intake and full exhaust, fmic and new radiator......anyway good luck to you and ill let ya know if i find anything out...

gcbutter

I put the RX7 on a Uhaul auto-transport and took it to North Carolina (4 our drive). I took it to a RX7 Guru (Steve Osley). Simply Amazing!!! What took me Three months of messing with, he figured out in 20 min. what the problem was.

First he did a compression check on the motor (results were great 8.0 - 9.0). So next he checked to make sure I was getting spark (I was). He then took a look at the First rotor's leading spark plug after we started the car. He found that there wasn't a single drop of fuel on the plug. He simply said your wiring from the primary fuel injectors is not connecting properly to the harness. I left the car there with him and made the 4 hour trip back home (had to go to work the next day).

The very next day (in the afternoon) He called me up and said my car was done. happily my wife and I made the trip back there and picked up my car. Steve went as far as hooking up the Datalogit and fixed my "Fan on/off temps" and fixed other little things he saw. Long story short, my car runs better than ever. I will find out exactly what he did with the wiring on Tuesday for people that are curious.

Agian, Steve Osley is the man who knows his stuff, and does not charge an arm and a leg to fix your 7. A matter of fact I gave him more than he was asking; for such great service, there was no reason not to.

Garrick

Brainfire

Oh, to be as gifted as that with an RX... like you, my nearest specialist is about 4 hours away - I live in Scotland, and he's in England!

Always glad to hear a happy ending... good luck.

9320bfd

gcbutter when u were having these problems, did u have an engine service light on. just wondering cuz im having the exact problems myself, and was wondering if mine is the same thing.....but im confused why its the primary injectors, shouldnt it be the secondarys if they are cutting out at 3500 rpm... just a question im not doubting u.

gcbutter

^^

Sorry, I did not have a check engine light. The car would start and stumble like crazy. It got to the point were the car would start and then stall. The cutting out at 3000 - 3500 was weird however, not sure why. let me see if Steve Osley can chime in on this thread to spell out what the problem was, and how he fixed it.

stevenoz

iTrader: (27)

Basically his front primary injector wasn't firing due to a poor connection in the harness. The rough idle was because the motor was only running on one rotor ( the rear ). Same symptoms as a blown motor or fouled plugs on one rotor. At higher rpms/load the front secondary would kick in causing an unsafe condition.

gcbutter

^^

There you go! Spoken for the man himself...

Kas

I had the same problem and it was my injectors ,and they didn't trigger the check engine light either.