JDM imported h23a bluetop in 5 gen prelude, converted to obd1, p28 chipped with phearable chip. Made a jumper harness to use the internal coil dizzy. Ran great. Shift cable snapped causing a misshift from the top of 3rd to 2nd. Car shut off at idle and would on stay running about 2k. Compression test=failed, took cylinder head off, bent valves. Brand new valves installed, cylinder head reinstalled. In down time made an engine tuck harness like I make for all my vehicles. Went to start it up, the car starts for second, dies, and the code 4 turns on. Can start and keep running if kept above an idle. Used shielded wiring for the appropriate dizzy wiring so that rules out. The resistance of my ckp is 347. Is this a bad sensor then? The dizzy worked before I pulled the cylinder head to replace the valves. Getting voltage at dizzy, no resistance to ground=no short.

 

Did you replace the crank sensor?

 

You cant replace a crank sensor in a dizzy.

 

Update. Car will idle very poorly with the obd2 h22a4 ecu with no ckp code. This makes no sense at all

 

It might take a while for the code to set again. You can swap out internals with another distributor but I'd check your wiring all over and use these two charts if it comes back

https://honda-tech.com/forums/honda-civic-del-sol-1992-2000-1/95-civic-limp-mode-tps-ckp-cel-codes-please-help-3040811/

 

I used the appropriate charts for a Prelude. Does it sound like the sensor itself is bad? its only readin 345 ohms instead of 350-700?

 

Check the 2 CKP wires and the sensor for a short or open. If all tests are fine, then swap in a known good ECU.

 

ckp is ohming out at 356 now and there are no shorts or opens. Tried a different p28 and still code 4

 

Your electrical tests most likely missed an open or short in the CKP circuit, or that the open or short is intermittent.

Detail exactly how you are doing the electrical tests.

 

I followed the exact procedure in the shop manual for the Prelude. Checking at ecu connectors and at dizzy connector.
Dont think this makes a difference but I used a small 10 pin Ampehnol mil spec connecotr for the dizzy connector on my harness.
Also, is there any chance that if the shielding around the wires wasnt grounding out correctly that it would cause this?

 

It's easy to check the ground for the shielding.

Is code 4 still thrown?

 

Yes still have a code 4. How do I go about checking if the shielding is grounding correctly?

 

Continuity to body ground at the shielding.

 

Since shielding is grounded through the brwn/blk wire which runs from ecu to thermostat ground, its never making contact with the chassis, so wouldnt you need to to continuity from ecu or therm. to shielding? The ecu also grounds itself at the thermostat, right? Or does it also ground at the chassis?

 

Have you tested whether there is continuity to body ground from the shielding?

 

If there is continuity to chassis from shielding, would that be bad or good? Since I said about therm. ground and ecu ground. Im starting to confuse myself here

 

Continuity to body ground at the shielding = good.

 

Alright, Ill check

 

Theres continuity to chassis at the ecu side of the shielding surrounding the dizzy wiring

 

The shielding is fine if you measure continuity to body ground from the shielding itself.

 

Yep. So no what? Thats another option out the window.

 

If you reset the ECU to clear the codes, does code 4 return as soon as you turn the key to ON(II) without starting the engine? Or do you need to run the engine to throw the code?

 

Need to run the engine to throw the code

 

map sensor?

 

What does the map have to do with the ckp