Issues with swapped JDM H22A into 4th gen AT Si - Honda Prelude Forum

ImportObsession · 03-04-2005, 06:06 PM

Okay, a buddy of mine after having problems with a shop forever finally just took his car back and gave it to someone else to get it at least running.

He swapped in a JDM H22A into his 4th gen Prelude which was originally an automatic Si non-vtec.

Here's the problems in the order I've notice them...

1.) The car cuts off right at the original redline. i.e. He still has the original guage cluster in there, and the car pulls fine and feels like it is just starting to open up when you hit the red on the original cluster and it cuts out almost as if you were pegging off the limiter.

2.) speedo does not work.

3.) VTEC may or may not be kicking in. For a car with all major boltons (CAI, header, exhaust, etc.) you can usually hear when it switches over and VTEC engages. It does not sound at any point like it's kicking in. However, on the other side, it pulls strong all the way to the 6500 redline. Usually if there is a problem with the solenoid (i.e. oil, pressure, ground, etc) it goes into a limp mode and the car just stops pulling. this is pulling just fine, it's getting cut off by the original rev limited.

those are what I think of off the top of my head. the way it SOUNDS to me so far is that the car is using the original ECU. would this not be the case with the rev limit, lack of VTEC, etc. take into consideration it was originally a non-vtec auto. then again, it may just be an oil related thing or a problem with the solenoid.

anyhow, it's night time and I haven't got a chance to compare the ECU serial to that of the engine to make sure it is in fact the right one, but what do you all think? is it something more obvious, etc?

thanks for the help.

EDIT: It is throwing a CEL, however we haven't looked to see what code, etc. He just got the car a couple hours ago.

EDIT 2: The car will start from the off position WITHOUT the clutch pedal being depressed. Again, what would cause this, ECU? The car should only start/turn again, with the clutch pedal down just like a normal MT car, right?

red92si · 03-04-2005, 06:14 PM

If speedo doesnt work... the VSS is faulty. A faulty VSS will cause the engine to run like crap since the ECU doesnt have a correct speed reading to go off of.

Get the CEL code(s)... it will help narrow things down, but Im pretty certain the VSS will have to be replaced.

ImportObsession · 03-05-2005, 12:46 AM

yea. I got the same response on other boards as well. we are going to rip it apart in the morning and try to undo what's been done and fix problems one by one. this is why I told my friend to take it to an actual shop instead of "some guy" who "knows what he is doing". argh. oh well, not my car.

thanks for the input. update as soon as I verify the ECU, and then onto the codes, etc.

red92si · 03-05-2005, 01:45 AM

My VSS went out a few months ago... so I know the pain.

aneurysm · 03-08-2005, 11:31 PM

ummmm....I hear no mention of an ECU swap? Or did I just miss that???

You will need a JDM P13 ECU for that motor/ manual transmission. That would most certainly explain the problems.

However, when I did my H22A swap I had a similar problem when I missed connecting the speed sensor harness at the transmission housing. It created the EXACT problems you described. Ran pretty much like crap, with a little pull, no VTEC, and short rev-limit.

Check that out and see what's up with VSS system.

brad