luiml73

iTrader: (1)

wzup fellas,

Well my engine ceased this morning and I'm trying to figure out why. No compression in the front rotor. It's GSL-SE with a 89T2 engine. Here is the catch. I was forced to use a an (88'ecu and wire harness) because we could'nt figure out how to make the 89'OMP work with the GSL-SE front cover. So I used a mechanical omp, therefore needing a 88ecu. A few people told me that it would work fine, but now thinking if this was the culprit to my engine's demise.

Atkins told me.......You are using the wrong computer and that is probably the main problem 87-88 turbo is one era of engine and the 89-91 is another the spark plugs are in a slightly different location so it will not run properly.
Thanks, Jason

I had no Idea about the sparkplug thing.

Another problem I had was the TPS. The TPS on series 4 has one sensor and the series 5 has two sensors. I'm using the S5 TPS but only one sensor connected to the 88 wire harness because the plugs are different.How do I fix this problem?

Here is the last reason why my engine blew. Ever since I installed the engine, I could'nt get the car the accelerate after 3800RPM. I tried all the tricks crounding and everything but nothing. Drove the car like this for about 6 months. Three weeks ago I decided to check if my secondaries where coming on at all. What I found is that one of the wires on the injector plug was'nt making contact. So at 3800 only one injector would come on causing the car to run lean (I think).

I have the money to rebuild, I'm scared to blow the engine right away.

Any advice on how to fix any of the problems above would be appreciated.

Luis

Rotorific

iTrader: (1)

you need to get an s5 ecu/harness... you did alot of bad not using the correct series parts.

you say you used a mechanical OMP and therefore needed an s4 ecu?????????? im not flaming you but man what does mechanical mean and what does electrical mean. You didnt need an s4 ecu for anything the mechanical omp works by a rod.

You need to get an S5 ecu and then rebuild your motor. if you have the correct series parts then your good to go... sorry to hear your story.

13bpower

Yes, all that would definately cause problems. All a learning experience I imagine. You'll do it right the second time I imagine. Also there is no "good" reason why the s5 electrical OMP shouldn't work.

luiml73

iTrader: (1)

thanks for responding

the S5 ecu only works with the ecectrical OMP. If I would have used the mechanical OMP with the S5 ecu the computer would have gone into limp mode (I think) that's the problem

your saying I could have used the S5 ECU and a mechanical omp?

If this is true I'm going to kill my self!!!!!!!!!!

Rotorific

iTrader: (1)

yes and if there was a sensor that would go off you could have easily bypassed it or grounded it. I hate to tell you that part.

luiml73

iTrader: (1)

Thanks, I'll look into that the second time around


anyonle else have any input?

hypntyz7

A few ways to make this work:

1) trade or sell the 89 t2 stuff (injectors, tps, throttlebody, etc.) and get 87-88 t2 stuff. The older stuff is just as good (except for the turbo, manifold, and alternator) and much cheaper/easier to find.

2) use all 89 stuff, but with teh s4 OMP rod and throttlebody. Plug the s5 electric OMP in to the wiring, but dont bolt it to anything...so long as it's there the ecu should be ok with it.

3) use all 89 stuff including front cover, and make custom motormounts for the 2gen motor.

BTW< if I understand this right, you used a mechanical OMP but no rod to control it (the s5 throttlebody has no place for the rod, and you stated you used the s5 TPS which only bolts to the s5 TB). This means the OMp was closed all this time...no lube to apex seals. Might as well have been blocked off. There is your problem.

luiml73

iTrader: (1)

Thank god for this forum!!!!!!!!. I feel alot better now knowing what I did wrong.

I actually though of #2 but decided not to.....Damn!!!!!!!

thank's for the help guy's

luis

Luis

HAILERS

Just passing by........but I have never ever read one single post of a successful use of a series five engine without the electrical metering oil pump functioning. I've yet to see anyone write telling how they overcame the ECU not going into the so called LIMP mode because the metering oil pump was not functioning.

If you know how to overcome/trick the series five ECU into not going into the LIMP mode, please pass the information on.

Sounds like the engine was running way too lean to me, what with the secondary not coming online. I doubt the series four oil metering pump had squat to do with its demise.

Oh, I bet money I could make a series five tps work with a series four ECU. Sounds like you already did that. Just use the narrow band part of the tps.

And the ATkins thing you mentioned........I would have thought mabe the higher compression might make a difference....but not the location of the sparkplugs. I'll bow to them since they do this for a living and this is just a hobby for me.......but I have lingering doubts about that remark. Maybe I'll come around, maybe not.

hypntyz7

I just posted it. Run whatever you want to as far as actual oil injection, but retain the stock OMP connected to the wiring harness, and tie it back somewhere out of the way. The ecu is smart enough to know if it is there or not, and if it returns proper resistance, but apparently not smart enough to know that it isnt actually pumping anything. I have done this before, in order to test OMP's I am selling...disconect wire on my running s5 car, plug in to OMP and leave laying somewhere in the bay, and go for a drive.

Sure it was running lean, but not to the point of detonation/engine damage. IF the injectors didnt kick in, the engine couldnt move enough air to cause a problem, it just had no power. I have run engines with 2ndary injector problems before...

I dont, if the bitch wasnt working!! Like I said, from what I can tell, he just bolted it on but attatched the actuation rod to nothing. This means it supplied either a) no oil or b) VERY little oil (what would be present at idle) to the apex seals at all times (idle and driving/accelerating). IF the engine was meant to get the same amount of oil all the time, there wouldnt be an actuation rod or an electronic OMP to vary flow. HE was basically getting none...you think that's a good thing for the apex seals?

NZConvertible

Dude, you shouldn't go off on people until you get your facts straight. If you try to run an engine on the S5 ECU with the electronic OMP unplugged it will not work. The ECU will go into limp mode. If you're using a mechanical OMP, you have to use the S4 ECU.

As for not using the correct ECU, many people have transplanted S5 blocks into S4's and used the S4 front cover and OMP, ECU, injectors, harness, etc. I doubt this was the cause of the problem.

The believe the S4 and S5 narrow-range TPS's are the same (the S5 has a full-range one also to run the OMP), so as long as the right one was plugged in, that shouldn't have been a problem either.

The unplugged secondary injector might have been part of the cause, but not necessarily. A mixture lean enough to cause detonation is only a small percentage down on the amount of fuel required. If one injector isn't firing then that rotor is only getting half the amount of fuel it needs, so the resulting combustion is not hot enough to cause detonation. There's just no power.

luiml73, you might have just been unlucky with the engine you got. I suggest you get the engine rebuilt, make sure all inbjectors are firing and then get onto a dyno. That'll show up any fuel mixture problems.

luiml73

iTrader: (1)

Everyone here is making really good points. I wonder if anyone else has installed a S5 into a first gen.

I'm going to print this thread for sure

Thank's again guy's

HAILERS

hypntyz7
Well, I must be wrong then. What in the world are all these series five people complaining about then? I've yet to see anyone post how they tricked the ECU. I'll read what you posted later. What is the resistance that the ECU is looking for then? But that must be in a series five fsm. I'll look.

It's like this. I'm thinking *you mean all those poor dumb ***** wern't smart enough to figure this out*. Hard to believe....but must be so.

Oh yeah. luiml73 didn't just fall off the hay wagon. I just KNOW he connected up the oil metering pump rod. You did, didn't you luiml73? Of course he did. Never occured to me that he wouldn't. Not for a nanno second.

luiml73

iTrader: (1)

Yes I did the car would not have lasted this long.

hypntyz7

It is variable resistance depending on stepper motor position. That is why you cant do a simple circuit to replicate it...the motor itself is the only thing that can. IF you leave it hooked up, the motor still responds to the ecu back and forth, it just doesnt know it's dry.

Perhaps he rigged up something, but he says he used the s5 TPS. the s5 TPS wont bolt to an s4 throttle body. The s5 throttle body has no place for the rod to connect to. So what did he do??

luiml73

iTrader: (1)

It's rigged

check this thread tomorrow I will post closer pics of everything as I take it apart




look what else I found from a different thread

Originally posted by RacerX7fb
Did you use the SE front cover? What did you do for the OMP? Ive been considering to do the same swap for awhile and a freind of mine has been working on the same swap. He had aluminum welded onto the SE front cover then tapped in threads for it to fit.. looks OEM too
--------------------------------------------------------------------------------



Actually a guy made my front cover for me. I started with a 12a cover from a 85 GSL, and he made threaded holes that allow me to mount the 89's electric OMP perfectly! Hey may have welded them, or me may have just drilled and tapped them. I honestly dont know.


__________________
1985 RX-7 GS:

Now I really want to kill myself.

Oh well, atleast now I know It could be done

HAILERS

Wish I'd a done that to my 82 before giving it away. Oh well. Off to sleep.

Rotorific

iTrader: (1)

First off im not some ******* ******** like everyone else on this forum and i clearly stated i was not flaming him....NO you dont need an S4 ecu but i didnt explain it clearly. this is more of what i meant.

It does work!

luiml73

iTrader: (1)

Hey Rotorific, dont worry I know you meant well.

I decided to buy a Microtech LT8, so I can port the new motor and tune it properly.


Thank's for all the input fellas

Luis

Terrh

iTrader: (7)

What's up with this spark plug thing? I'm running an s5 block with s4 front cover/ecu/everything else
my car runs fine (have some issues, but I really doubt they are ECU related)

I'm not going to have problems, am I?

dr0x

The plugs are closer together on a s5. As long as you are running 2 s5 housings, and not 1 s4 and 1 s5 youll be fine.