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Help diagnose

Old Jan 1, 2009 | 10:24 PM
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Help diagnose

I searched and read a few threads .. and just as it seemed I found my answer everyone stopped responding in those threads lol.


About the car:
1000 miles on rebuild
Nonsequential

Anyway here are the symptoms:
-As soon as car hits 0 psi it runs like ****
-Idle sits at 1500 (might be the large streetport i have though)
-Backfires a good amount
-CEL is on, but is giving a ton of crazy codes which I know can't be right since what its saying is wrong has been fixed already.
- Runs super rich (only getting around 145-155 miles a tank)



I've tried the following:
1. Tightining all the couplers including y-pipe (although they were loose ... didn't seem to really do anything)
2. Reset ECU ... currently doing it now, but don't think its going to help much since I reset it right after coming out of the rebuild and still did the same thing (granted the CEL went off for about 20 miles but eh .. that doesn't mean **** on these cars lol).

Opinions? .... TPS, MAP, etc.
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Old Jan 1, 2009 | 11:08 PM
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Also seeing some smoke on start up (smells/looks like gas)
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Old Jan 1, 2009 | 11:17 PM
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has it been doing this just since rebuild? what kind of codes are you getting? could it be something as simple as a bad ground causing ecu to act up?
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Old Jan 1, 2009 | 11:24 PM
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You checked the map sensor I assume?
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Old Jan 2, 2009 | 01:27 AM
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map sensor appears to be fine. will doublecheck again tomorrow or this weekend with a multimeter though.

and yes since the rebuild its been doing this. engine has good vacuum though (around 15) .. so im sure its fine.

we tried swapping ecus and it still did it .. so i dont know? I have the FSM printed out so ill trace all the grounds and see how they look.
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Old Jan 2, 2009 | 08:41 AM
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You are in limp mode for one. Did you install resistors when you went non-sequential? If not it will go into limp mode immediately. A faulty knock sensor or bad OMP will cause limp mode also.
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Old Jan 2, 2009 | 08:48 AM
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Originally Posted by hurleysurf24
-CEL is on, but is giving a ton of crazy codes which I know can't be right since what its saying is wrong has been fixed already.
What are the exact codes that it's currently storing? Which ones and how did you fix them?
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Old Jan 2, 2009 | 10:44 AM
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Check resistance on the primary coil.
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Old Jan 2, 2009 | 12:57 PM
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I have the following codes;
25, 26, 28, 31, 32, 33, 34, 38, 39, 45, and 46 lol
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Old Jan 2, 2009 | 01:00 PM
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Note all emissions have been removed and uneeded sensors . So thats probably the reason fort mosst of the codes popping up.

25 Solenoid valve - pressure regulator control
26 metering oil pump stepper motor
28 Solenoid valve - EGR
31 solenoid valve - relief 1
32 Solenoid valve - switching
33 Solenoid valve - port air bypass
34 Solenoid valve -idle speed control (BAC)
38 Solenoid valve - accelerated warmup system and air supply valve
39 Solenoid valve - relief 2
45 Solenoid valve - charge control
46 Solenoid valve - charge relief control
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Old Jan 2, 2009 | 01:12 PM
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SO you removed the connectors and didnt install resistors and you are tyring to run the stock ecu? You HAVE to use resistors, it is not an option.
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Old Jan 2, 2009 | 01:41 PM
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You really should use resistors for the solenoids you have removed. However, most of those won't throw the car into limp mode. The one you REALLY need to take care of is #26, which you cannot do simply by using resistors.
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Old Jan 2, 2009 | 01:53 PM
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i didnt do the nonsequential mod ... the shop that had it did. Is there a writeup for throwing on the 330 resistors?

I think that is going to be a rather large problem. It explains all 40 codes that are coming uip . As for 26 ... hmmmm what would cause that, or how would I test it (is there a page on the FSM for it?).
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Old Jan 2, 2009 | 02:05 PM
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Section D in the FSM (Lubrication System). In the 1994 manual, the diagnosis part starts on D-14. Should be the same or close to it on the 93 or 95 manual (whichever you have access to).
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Old Jan 2, 2009 | 02:14 PM
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Thanks. So I should just buy an entire new OMP? Or is the sender something seperate I can buy and install.
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Old Jan 2, 2009 | 02:16 PM
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thanks djseven for the advice!
Is there a write up on installing resistors ? (I'm not too elecrically talented here lol).
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Old Jan 2, 2009 | 02:28 PM
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Originally Posted by hurleysurf24
Thanks. So I should just buy an entire new OMP? Or is the sender something seperate I can buy and install.
You might search, but as far I know most people end up replacing the OMP. The problem is that it's damn expensive new, somewhere around $1800. I would start by checking the wiring to the OMP. If the wiring checks out, then look for a used unit (try PM'ing Fritz Flynn).

Originally Posted by hurleysurf24
thanks djseven for the advice!
Is there a write up on installing resistors ? (I'm not too elecrically talented here lol).
For the female solenoid connector sockets you just put one end of the resistor in one side, the other end of the resistor in the other side to make a bridge. The resistors I had were a little long so I just cut them down to fit better. Then just wrap the connector with the resistor in place with some tape.
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Old Jan 2, 2009 | 02:34 PM
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BTW, in case you do need to replace it:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/changing-oil-metering-pump-omp-while-car-my-how-675341/
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Old Jan 2, 2009 | 02:44 PM
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I just popped in to point out that 15 inches of vacuum at 1500 rpm is actually pretty poor and certainly doesnt mean the motor is healthy, but a combination of the large port and the car running uber-rich in limp mode is probably the cause for the low vacuum, I wouldn't look to the compression of the motor as suspect at this point.

I have to ask, what shop let the car leave in this condition?
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Old Jan 2, 2009 | 02:57 PM
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so let me get this straight... you're trying to get a car to run right w/ the stock ECU and a large street port?
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Old Jan 2, 2009 | 03:40 PM
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i know its not going to run 100% but it should be able to atleast get postive boost.
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Old Jan 2, 2009 | 03:59 PM
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Installing the resistors is extremely easy if the connectors or wiring for the connectors are still present.

If the connectors are present, you can crimp on or solder on male spade connectors on to the end of the 330ohm 1/2 watt resistors and plug the male spade connectors into the connectors on the wiring harness. Do this for all the colored connectors that control the sequential and emissions equipment. ( one day I will figure out which ones cause limp mode but I havent spend the time to find the exact ones at this point).

If the connectors have been cut, solder/crimp the resistors directly to the wires in teh factory wiring harness for each connector.

If all the wires have been removed, time for a new harness if you arent good with wiring/electrical

If you need a good omp, I will sell you one for $45.00 SHipped. If you dont want to fully replace the omp at this time you can just plug in a known good one and tie it out of the way so the computer is happy and just premix for the time being. With the car being non-seq and likely emissions deleted changing the OMP is a breeze.
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Old Jan 2, 2009 | 06:30 PM
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thanks for the advice again !
will get to doing this soon.
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Old Jan 3, 2009 | 03:51 PM
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UPDATE:

I love rx7club Thanks to everyone and some of my own logical thinking the car is now running INSANE (still needs some adjustment but atleast I can hit ~8-9 psi).

Threw resistors in .. and bam fixed.
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Old Jan 3, 2009 | 04:00 PM
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Originally Posted by hurleysurf24
UPDATE:

I love rx7club Thanks to everyone and some of my own logical thinking the car is now running INSANE (still needs some adjustment but atleast I can hit ~8-9 psi).

Threw resistors in .. and bam fixed.
if you need an OMP i just removed mine and it was working just fine when i removed it. i removed it about two weeks ago.
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