hacksword

Ok... Here goes. I am a total noob when it comes to working on this car, but I love it, and I would like to solve this problem without taking it to a shop.

I start the car, it idles just fine. Once I let it warm up, I can nail the gas (before driving anywhere) and it will go up to redline without an issue. Sounds great, feels great, smells normal, no smoke.... Now lets say I want to drive it. I can get about a city block, everything is totally fine up to this point. Without any kind of warning, my Check engine light comes on, and then I get severe hesitation if I try and drive it harder than my grandma would. If it drive it really easy, I can go... just not any fun. The light stays on. I can rev it up to 6k, if I rev it real slow and easy. If I try and punch it, I get almost no power, it sounds like it is sputtering, it will still accellerate, it is just horribly slow.

Now here's the kicker. When I am having this issue, I can turn the car off, then right back on.... I can race like a pro for about 1 block, no issues, no lights, no hesitation. The engine light comes back on.... no fun anymore.

Any help would be great. My brother-in-law is coming over today, and we are going to check vacuum and TPS. I will post anything I find out.

lastphaseofthis

iTrader: (8)

oil metering pump, OMP, It's been beating to death, go buy a USED OMP out of the for sale section. welcome, theres a **** tone of information about limp mode already on this forum, search "limp mode" or "S5 OMP".

hacksword

Could this be something as stupid as an oil change/replace oil filter? The car sat for almost a year, snow/ new baby in the picture. The 7 sat in the driveway collecting dust. Today was the first day I really tried to take it out in a long time. Let me know what you think. OMP's are pretty cheap, so I think I am going to pick one up anyways.

Lets say it is the OMP, is there anything I could do as far as taking it apart and cleaning it or something?

Thanks alot for your reply.

HAILERS

It's an electrical problem INSIDE the OMP unit most likely.

Download the engine fault codes to be sure.

There is no known cheap fix for this.

SEARCH for LIMP MODE and OMP. Hundreds of threads on this item. All series five of course.

Ain't no oil change/filter problem related item in any form or fashion.

lastphaseofthis

iTrader: (8)

No.

"-TEd"

hacksword

Rock on, I am going to see if I cant get an OMP here locally, I have also read that the OMP when it fails it takes out the ECU, is there anyway for me to test this quickly? If they are both bad, I would like to grab them both, if I can save some money (the wife would love that) then I will just go with the OMP.

Thanks again guys for being so patient. I know I am a noob as previously stated.

lastphaseofthis

iTrader: (8)

is your ecu bad??? your car starts... here's your sign.. d

rotary#10

iTrader: (38)

make a jumper wire and check the codes

hacksword

LOLZ, thanks guys. Like I said, I am a noob and I wanted to cover all my bases.

jackhild59

iTrader: (7)

http://www.rotorwiki.com/index.php/89-91_Error_Codes

This thread (along with the FSM) will help you pull the codes.

This thread will also teach you how to properly diagnose all the known failure modes of the electronic MOP.

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/s5-mop-ecu-failure-diagnosis-710938/


If your ecu is burned, the car will still run and behave as you are describing. If your ecu is not burned up, you should stop driving it now or you will burn up the ECU. Pics in the following thread showing the burned sections of the ECU. It is very distinctive. Mine looked *exactly* like those in the pictures.

hacksword

Thanks alot Jack. Great Info. I am a pictures kind of guy.

bac22

Yup...same exact problem...just opened up my ECU and burnt resistor and fired Tosiba MP4501. So I'm now on the hunt for an ECU and MOP myself.

hacksword

I found both on ebay, moderately priced. I am scared about the OMP though. I will let you know. Says it was good. We will find out. If not, im getting a RA kit and premixing :/