So your car is idling fine?

It only bogs under acceleration?

Have you boosted it or floored to see how it runs under boost?

You disconnected the o2 sensor and the car idles fine?

you drive it with the o2 sensor diconnected and the car doesn't behave any differently?

If all this is true then you have some sort of engine harness or ECU problem.

I'm pretty sure a stock FD with stock ECU will idle very ruff even like it's on one rotor and smoke without the o2 sensor connected.

Give us all more details about how the car runs idles etc.....

 

Now, I talked with a forum member who told me that it doesn't matter which rotor you connect your leading plug wire to. So, I believe that I have the L1 connected to the rear rotor leading plug, and the shop foreman at Malloy told me, "no way, L1 goes to the front rotor, and anyone that tells you it doesn't matter is wrong and it will cause the car to run like crap"

trev

 

Yep i suspect switching the leading ignition might cause a problem because the rotors fire at different times

Damn good thing you decided not to boost it

 

Nope , the leading plugs BOTH fire at the same time in wasted spark mode , its the trailing plugs that you need to be careful with . Just for the record , I ran my car without an O2 sensor for more than a year with no problems what so ever ! You can also look at your Knock sensor , if its disconnected or bad the ECU will retard the timing .

 

I guess that makes sense considering they share the same coil but still a little freaky.

when running the PFC you can get away without using the sensor but I'm pretty sure I remember some serious havoc when running a stock ecu and forgetting to plug the o2 sensor back up.

That's actually pretty convenient thing to know

 

so you are saying that the Leadings can go to any housing? I will test that theory tonight

 

I If the knock sensor were the case, I would expect a check engine light to illuminate...

Trev

 

welp, changed the Lead wires around, and as mentioned, didn't change anything. my connector broke for the airpump (which again is on the car, but all capped off) so I would have to plug it in by inserting the 2 prongs into the airpump-side of the connector...would plugging that in have any effect? I know the airpump doesn't give any feedback to the ecu, but just a thought....i think swapping ecu's is next or testing the fuel pump relay.

 

If this knock sensor were causing the issue, wouldn't I have a CEL?

 

Alright, so I swapped out my 93 cali ECU for a 93 non-cali remanufactured ecu. I erased codes and checked for them with this ecu. I am still getting 30, 33, 38, 39. However, I am NOW getting 51 (fuel pump relay) I did some testing of the relay itself by removing it and connecting a direct 12v souce to terminals A and B on the relay. It made the clicking noise I anticipated it would. With voltage connected, I checked the resistance in ohms between C and D and sure enough it was zero as I expected. Relay checks out. I put it back in. For kicks and giggle, I jump F/P and GND to make sure the fuel pump is operating. That was good. I removed the rubber fuel feed line and tested it...it didn't **** the fuel out with pressure, but it flowed well enough to fill a coffee mug in a matter of 3-5 seconds. Fuel filter is new. So, I went to start it. It cranked and started for about 2 seconds and died. I tried again, but just cranks. I thought it could be flooded. Waited till morning and tried starting...still just cranking. I will swap out ECUs again and try. I guess I am wondering why my stock cali ECU didn't pick up on the 51, but the non-cali did....as soon as I put the other ECU in, I will check the codes again. If i don't get a 51, I will remove the f/p relay and see if it gets one then...any ideas?

 

ttt

 

When I purchased my FD it did not boost at all and broke up all over the place. The symptoms were similar to yours. The car would idle fine but would buck, hesitate and stumble all over the place just driving around. The whole time it was the secondary injectors clogged to ****. I swapped them out with a friends and the car ran perfect and boosted great. Just something to check thats decently simple. Good luck.

 

Good idea, but my injectors are only 8 miles old since I got them cleaned and flowed at RC eng.

Trev

 

Right, but that still could be the problem. RC uses a varnish solution to clean the injectors, and (especially when they're not immediately installed) they can become stuck open or closed. I would take them out and apply voltage to them to see if they operate properly. Could very well be what's wrong.

 

If you are still getting code 51 and the relay itself checks out, then it will be time to spec the wires running to the relay. I would imagine that if you are having issues with the fuel relay, that would account for some issues trying to put load on the car.

 

I will test out the wiring to the relay first and clear that. I will also put my cali ECU in and see if I can start the car...right now I can't get the car to even start...just cranks...

Trev

 

Okay, put the cali ECU back in...no code 51 anymore and it starts right up. The ECU I was trying was a 93 non-cali remanufactured ECU ( I assume replaced under a recall) Anyways, I connected voltage to the F/P and was getting 9.4 at idle and under light brisk acceleration, I was dipping to 8.8 or 8.9. I wiring a temporary direct wire from the battery to the red/white wire at the fuel pump and got 10.75 volts. I still have the stutter and hesistant doggy acceleration though. I only have a code 38 (AWS)...going to check BOTH fuel pump relays...I used a voltmeter/ohmeter on the fuel pump resistor and got 0.9 ohms which is 0.2 out of spec of the factory suggestion. I don't know if that is an error with the ohmeter though...I would need a flukemeter I would think to be totally accurate.

 

ttt

 

I checked the circuit relay by applying voltage to terminals A and B and ohming out C and D. When I applied the voltage, it clicked like it should and it was registering 00.3 on the ohmeter. I need to get a second person to listen to the relay and make sure it is clicking when I turn the Ign on to verify the wiring is good going to it...after this, not sure where to turn...Is it possible that the filter ON the fuel pump can get clogged?

 

Yes - if there's a filter anywhere, it CAN get clogged.

 

i would assume that would be an issue. I think I need to get a fuel pressure gauge and see how my fuel pressure is...that will tell me a lot.

Trev

 

Did you change your wiring harness when you did the motor? Given this and the low voltage you are seeing to the fuel pump, it almost sounds like serious electrical problems from an old, bad wiring harness.

I had some funky problems on my last FD due to a bad wiring harness....

 

harness is original...and yes...I am considering this as a problem...a 700.00 problem! I have not ruled this out unfortunately. I will see if there is a fuel pressure issue still...then go after the harness

 

Yep, that is an expensive problem that many of us have encountered...

If you are checking fuel pressure, remember that the wiring might contribute to that. You might want to wire directly to the battery temporarily to help determine the cause of any fuel pressure issues you may be having.

Good luck.

 

I've seen several people have problems with recently cleaned injectors.

I'd test the secondaries and or swap them out.

Good luck