Acceleration Problem on S5 N/A
 

I have a 91 vert N/A. It starts fine, idles fine. When I drive it, 1st gear to about 5k it does fine, then the check engine comes one and I loose all acceleration (kind of if the secondaries were not working). I have checked for vacuum leak near the AFM and nothing.
Now if I remove the cone filter and control the amount of air (with my hand) I can make it accelerate properly. If I disconect and reconect the wire to the AFM or map sensor it will turn the "Check engine" light off.
Whats wrong????:confused:

This will get you started: Click Here

I took it to the shop and it doesn't generate a code. Seem that when I turn it off and back on it will reset rhe "check engine" light.
It also does this problem under a load. In other words, if I start it and mess with it while parked it won't do it.

Yeah... now get down on your knees and pray to god, Allah, Buddah, Ieohvah, whoever.... that it isn' tthe OMP.. If you get the dreaded OMP, 27 or 28 if memory serves me correct, take the ecu apart and look for a fried PC board as well!!!!

after see your last post.... take the ECU apart and look at the board.. i had the exact same problem.. turned out to be a fried ECU and a bad OMP..... (well, i switched the OMP just to be safe)

IF the Board is fine.. switch out your MAF... could have a dead spot..

If it would store a code that would help but it doesn't.
I took it to the shop while the "check engine" light was still on, however in order to retrive codes the car needs to be not running and the key in the start mode.
Like I said, once I recycle (turn it off and then on) the "engine light" goes off. If i drive it once I reach about 5k and shift the light comes on, the car sputters and I have to take the foot off the accelerator and accelarate slowly to gain any speed.

Thanks "Years of decay"

When I open the ecu will I see a burnt spot?

Even after the check light goes out, the code should still be stored until you unplug the ECU or disconnect the battery.

Thanks "SureShot"

That is what I would think too. Because it is not storing a code it makes me believe it might be something to do with fuel pum or fuel pressure.

I have now replaced the fuel pump, tried a different TPS, ecu and AFM. Still have the same problem.

I was able to retrive some codes with the car running. They were:

10
13
07

I can't find what code "07" is.
Can anybody help??

there is no code 7...

it doesn't matter if the light is on or not. the code is still in the ecu and doesn't go away untill the battery is unpluged.

if your light is comming on. but after you turn the car off. you can't check for codes using the above method. then I'd say either the light or ecu is screwed up.

Scott that is what I thiugh when I looked at you site. I tried a different ecu and was still getting the codes. Perhaps Iam conting the flashes wrong, but when I turn the car off it won't generate any codes. I thing I will take it to the shop on tuesday so the scanner can tell me the codes.

OK...I took the car to the shop. Ended up I was reading the codes wrong.
The shop ended up with a CODE 27.
I guess "Years of Decay" hit it right on the nose.

Now can somone PLEASE explain how to fix the problem?

Thanks

First of all... I wouldn't drive your car until this is solved, JUST IN CASE it IS the OMP. You can suffer not having a car vs a 2K+ rebuild...

Under the passenger floor board, under all the carpet is where the ECU is stored. Search on RX7club to find out exact instructions on this.

Now once you get to the ECU, I have no clue..:confused: I don't know if you can take them apart, or what... if if they'll even "look" burnt.

Is there a way to check the OMP?

If the OMP turns out to be working... replace the ECU.

While you got the ECU out... do some grounding work too :)

i had the exact same problem, and my computer wouldn't store the code either. soo...i ran it until the error came on, popped the hood, plugged in the check wire (actually Ted did, for some reason i didn't think to check while the car was still on), and it spat out code 27. for some reason turning off the car would reset that code. 27, metering oil pump....new one 1200 bucks...used maybe 50-200 depending on where you find it. i found a used one, plugged it in and zip tied it to my strut tower brace. now i am running premix.

so, Drive the car until it errors, then plug in the check wire and watch for #27.

edit: also the factory shop manual provides resistances for the metering oil pump you can test with a multimeter to see if yours really is busted or not.

edit again: the reason i didn't hook up the omp is because i don't mind running premix, in fact it may be in my head but my gas milage went up with premix. also, heat and vibration kill electronics, and the oil metering pump doesn't really "pump" anything so it won't burn itself out like a normal pump. it seems to be perfectly happy being zip tied to my strut brace and plugged in.

Yesterday I changed the OMP , reset the computer and the code came back. I will try checking for continuity from the OMP to the ECU.

Any other sugestions

Yesterday I checked continuity and it is all fine. Replaced omp again (with a know working one).
Still have code 27. How could I check for the ECU?

Just a suggestion b/c I had that same problem , check your o2 sensor.My car does that when the 02 sensor comes unplugged from the extension wire.{I put my RB headers on and forgot to secure the sensor extension wire so it is now melted to my headers, oops!}

if you HAVE to drive the car. put some 2 stroke oil in with the gas (nows a good time to read up on premixing) just to keep you safe incase its an OMP failure. this will save you from a rebuild if the omp crapped out but you still HAVE to drive it.

can i get an update? I have a similar situation. I want to see how he fixed it.

bump

:cool:

if you oil metering pump is bad it might still be ok to drive it. my omp is bad right now but i have been driving my car for about 7 months with it like that. my 1990 rx7 gxl has an electronic oil metering pump that has a fail safe that when it goes wrong it continually pumps oil so that you won't screw anything up. because of this continuous pumping my car will not pass emissions, my hydrocarbons failed horribly. i am having trouble finding one in the dallas area right now. the cheapest i have found it for is 350 and the dealer wants 1600. i was told this by a guy who is an airplane mechanic and worked on rotary planes at one time. this may be true and it may not but my car is still running. my light comes on and i just turn it on while i am driving and turn it back on. my light comes on about every 15 minutes or so and i can rev it to 8k no problem but i do feel that i have a little performance loss because of this and my idling sucks. food for thought

this seems to be similar to my problem...
it started last week with heavy "jerks" above 4000rpm
but not everytime i drive. now however it is almost everytime i drive and it has also happend below 4000 a couple of times now. its just on load mean i can rev it up without any problem and i dont have any warning lights showing. only mod sofar is an open cone filter... (had the car for a month without problems so i started spending all my money on buying mods and then i starts screwing :mad:

would be happy for any help i can get!!!

/crille (SWE)

-89 RX7 TII vert

"lucifergus".. check the OMP. I too could rev it without a load without problem. Even when driving if a I would go above 4k it would do fine. Everytime I turned the car off and started it it would reset my ecu and the check engine would go away just to come back after I went over 4k.

Rx7jones...I am in Arlington and got a used OMP for $50. If you feel you need one let me know and I will hook you up with my parts man.