i'm confused

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dirt817

Member
I just picked up an 89 hf with a 91 si motor in it and its throwing two codes. I get a 12 and a 17 with the engine running. I looked up the codes and it showed the 12 as an egr problem and the 17 as vehicle speed sensor. My factory service manual doesn't even have "egr" printed in any of the 681 pages and isn't the speed sensor just the speedo cable going from the diff to the gauges? I've looked the entire motor over and can't find anything resembling an egr valve or a missing egr valve. The speedo cable is installed correctly as far as I know. I was told it's using the si ecu and the stock d15 injectors. It runs fine, doesn't start up as nicely as it should, but idles perfectly and revs hard.

Is there something I'm doing wrong?
 
ok hf's have an egr valve si's dont so this means your running a hf computer because its still looking for it....go buy you an si computer...here is how to do the speed sensor go here http://www.hybridgarage.com/tech/manuals/E...rvicemanual.pdf click fuel and emissions on the left hand side. scroll down and click vehicle speed sensor. the manual tells you from there. you have to have adobe to view this link
 
speedo works fine. Whats the number for the ecu i should be using? Will I hurt anything by using an hf computer with the si motor?
 
Originally posted by ckyhimself@Apr 29 2004, 06:16 AM
u should be using an si ecu anyway otherwish ur not getting prime perfomance outta that motor anyways....

i second that....with that hf comp youll always have the egr problem ,secondly the fuel curve sucks, thirdly bunk ass red line.you need a pm6 it sounds like you have a pm8. get a new ecu and it might even solve the speedo problem
 
i just checked today, its a pm8 :angry:

I was also wondering why it wasnt shifting correctly so i put it on a lift at work today and saw that the linkage was put in upside down. I was also told when I bought it that the hf uses two vaccum lines that the si doesn't. There are 4 coming out of the black cover thing on the firewall, two are connected and two are just hanging there. Should I plug them up or connect them to something? The kid who put the motor in did one piss-poor job. The map sensor isn't even secured to anything, its just flopping around. Theres a couple wiring connectors not hooked up to anything. I'll try to get pic or something so we can figure it out, I'm stumped.
 
yea... jsut get some standard vaccum splitters....

(i have the same swap style in my HF)

i'm not 100% shure what the hell those lines are for but it cant' hurt to hook them up.... if you want i can take a picture or 2 of my TB / engine bay and send them to you if it'll help at all... let me know.. (pm me)
 
you can just put screws or somthing in the hose you"ll be fine you dont need most of them any way
 
A friend of mine(very knowledgable honda-guy) recommended I use an OBD0 ls ecu now. Is there any reason to do so?
 
no the pr4 is for a dohc motor. I don't think it will work. Also the ls is a b-series motor, where the si is a d-series. I am pretty sure it won't work.
 
It will work.

My buddy ran a obd0 ls ecu in his sohc zc hatch for a day just to see if there was a difference. There wasn't really at all.

I've heard its the best for the dohc zc.
 
If you use a pg7 ecu from a 88-89 ls your car should run well. That ecu raises your redline and gives you a more aggresive fuel map. If you want you can also take the pg7 board out of the case and put it in your case so that your bolt holes line up. I don't think that the pr4 form the 90-93 ls' will work, but i could be wrong.

Ben
 
LS ECUs dump too much fuel for D series motors, even ZC.

if you want to add a couple of riceboy points, go ahead and use one.

Of the STOCK ECUs (i.e. not chipped)

D16A6 Si run best with JDM PR5 (SOHC ZC)
ZC run best with JDM PM7 (DOHC ZC)
MPFI converted D15s run best with PM6 (USDM Si) / PR5 (SOHC ZC) depending on what else is done.

Chip it + tune it. Don't fuck around with retarded ass wrong ECUs when the tools are out there...
 
Ok, I got the PM6, but now it won't start. It fires up every time with the PM8, but if I connect the PM6 it'll run for a second then immediatly die out. The kid I bought it from told me its a 91 D16a6 with the 89 hf harness. Do I need the Si harness?
 
I would try another PM6. I run my B18B in my 91 CRX HF with a HF engine harness and chipped 91 PM6 ECU. It sounds to me like you got a bad ECU. 88-89 teg PG7 will also work well, 90-91 teg PR4 will work in a pinch, but is not intended for PM6.
 
My buddy came up with a theory to why it isn't working right.

With the hf ecu in it, it'll run fine, but throw a code for crank position sensor. He said hf ecu's don't care about that sensor, so it'll run with the sensor being bad. The pm6 uses that sensor, so if it isn't working then it won't let the engine run.

I was planning on buying a new distributor anyway, but does that make sense at all? I don't have access to another pm6 without buying one. No one out here has an old SI.
 
Crank position is a pretty serious code. If you still have issues after you get a new distributor, lemme know. I have a 88-89 Si ECU i'll let go cheap.
 
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