Bought the 91 LS motor from CL, the seller gave me an ECU and he said its belong to the motor. When i hooked up and find out its bigger than the others ECUs and won't fit in 4 bolts where used to mount it in, but it can start !
Does anyone have this issue ? if not , he must gave me a wrong one, then can I use my old 90 DX's ECU for 91 LS swap ?
Thanks, D

 

what on the tag of your ECU?

PR4

P75

 

they dont always fit, they didnt fit in my crx either

 

Thanks Guys !
will verify the tag when i get home.

 

BTW - your DX ECU will NOT work for the LS swap. The stock DX engine has a two injector (dual point fuel injection) set-up, whereas the LS engine/ECU has the 4 injector (multi-point fuel injection) as well as different inputs for other sensors too.

Is this swap completed? Did you already do the dual-point to multi-point swap?

 

Good point, you have to rewire for four injectors not the high and low with dual-point. Might want to wire in an injector resistor box at the same time, if you havent done so. You dont have to, but it is eaiser to find low impedance injectors rather than high impendance if you plan on building the motor at all.

Come to think of it you may not be able to wire the injector resistor box in, I think that the LS injectors are high impendance no? You will have to measure the resistance on the injectors.

 

Good points Guys !
i am almost done with the swap and just concerning about the ECU mounting fitment !
so far, the engine can starts but haven't ride it yet since i have to work on power steering hose replacement.

 

yea just check those injectors, i believe the 94-95 obd1 b18b ls motors have 235 cc injectors but they were high impedance, which would mean do not wire in a resistor box while doing the swap/build.

 

If obd1 p75 there is no need for the resistor box unless running bigger injectors....and to answer your question a obd1 ecu has the mounting points in different places than the pre-obd counterparts

 

Ok so what is the solution for his ECU then ? What's the best way to mount his teg ECU ?

 

I just have my p61 ecu on two of the studs and no nuts. It doesn't move at all.

 

The same way teamredline89hatch has his.....who cares how the ecu mounts anyways 1. Nobody is suppose to see it and 2. Its under the carpet it's not going to runaway

 

i got almost the same question but i got a ef si and i got a d16y8 for it what computer can i use for it can i use any of thr obd0 ecu or whst do i need to get
help

 

You could use a pw0 but still it is better to run a obd1 basemap to completely run correctly.

 

can i use one from the 90 prelude?? for the y8

 

You need to start your own topic and not clutter this one with your unrelated info.

 

BTW - not just no, but HELL no.

 

Ok guys this is the clip that we ( OP and I) recorded earlier from the ECU ....can anyone explain what does this means ? By the way , the tag on his ECU said " AR" so is this the right ECU for him to use on his LS swap?

http://s230.photobucket.com/albums/e...t=90897666.mp4

 

Been googled but don't see " AR" tag...
Anyone ?

 

Code 5 = map sensor

ECU Codes <-- clickable

 

No you want to check what the middle three digits in the part number are, as in "PR4" or "P75" or "PM6" etc. etc.

What are those on his ECU?

 

Thank you sir and we didn't look at the digit like u said but will update tomorrow . Now for the map sensor , what do we need to do on this ?

1) take it out and clean it?
2) replacing it?
3) or maybe we mixed up w the wrong hose?
4) thoughts?

 

I'd double check the wiring to the MAP sensor first.

 

I will do that but we are at loss on the vaccum line on this motor . Does anyone has the pictures to show where we should hook up all the metal hoses on the IM ?

We also noticed that the throttle response is very slow . It sounds like the intake suck alot of air then the IM rev it ... I mean it just takes forever to get to 40mph ( I really have to step the gas pedal down to get to that speed) . Could it be the vacuum line ?

 

Anyone? Common guys I know a lot of ppls have done with this motor before ...