Hey Guys,

I'm looking for help with an issue that im having with my 5th gen SE Prelude 2001. I consider myself mechanically inclined, but i just can't seem to figure out this problem.

So i've attached a video to show what happens at idle, when load is put onto the system and how the car idles. I cant keep the car running without a vac leak post TB. If I run the car without a vac leak, then when i turn the steering wheel, turn on the A/C, etc, it will shut off and i'll have a nightmare trying to get it running again.

https://www.youtube.com/watch?v=Vmsh...ature=youtu.be

So far i've replace the fuel filter, the whole dizzy (at one point it was giving a ICM code), main relay, took off the whole intake manifold and cleaned all the EGR ports and intake runs, cleaned the TB, and checked the TPS to make sure it was within the correct voltages, cleaned the IACV and FITV, and adjusted the valve lash.

I've run out of ideas I just can't seem to get this thing reliable. Please let me know what you guys think! Thanks

 

What ecu are you running and have you checked to make sure all you vacuum lines are all hooked up to the right ports and what not?

 

Have you checked the ignition timing?

 

What is it exactly that we're supposed to be seeing in this video ? I don't see anything wrong.

 

I still need to check the timing.. But the car will run fine when I create a vacuum leak to get it idling without dying. Furthermore, the car pulls really well while in VTEC.

It's the stock ECU all parts are stock except for intake, headers, and full exhaust.

I've checked all the vacuum lines and they are correctly attached.

The video has the car just idling and when i rev it up, and takes a while to adjust. When i turn the wheel at the end, the car just dies (I have all the vac lines plugged so theres no leaks).

So far I need to check:
Timing
MAP (How?)
o2 Sensor

 

We are suppose to be seeing how his idle fluctuates it happens around 40 seconds or so into the video the idle does its normal thing and then dips down to almost nothing that us what he is worried about and wanting to fix.

 

tested coolant temp sensor? main relay?

fwiw:

Starting Problems

 

Main relay is where I'd start. It seems its always a prelude main relay.

Oh, also.. there is a power sterring pressure switch. It adjusts the idle when the engine senses the PS load. I'd imagine there is one for the a/c too. So if yours is faulty, or going bad, it may not be compensating your engine.

 

Hey guys thanks for the responses.

So last night i changed out the o2 sensor, and now it's not starting at all.

Also, the main relay has been changed, it seemed to make a difference for the first day, but not anymore. Either way, I can hear the click for the relay, and the pump come on and prime afterwards when the key is turned to the on position.

I am also getting spark when I pull a plug off (with correct timing from the dizzy), as well as fuel when i pull the fuel line (although im not sure about fuel pressure, but it should still start with low pressure).

I'm sure the injectors are firing, but ill take a look at the voltages tonight and make sure it's getting the correct amount.

This is the weirdest problem, because I had no trouble starting the car after the main relay was replaced. Another possibility could be the ECU?

How do I go about testing the coolant temp sensor?

Thanks again, any help is appreciated!

 

once you can get i t started again make sure your base idle is correct, i dont have a service manual in front of me, but i would always check that the idle is within spec without the iacv hooked up, and then run the idle learn procedure as well.

 

sent you a link to fsm at h**ndahookup.

 

Okay interesting thing going on now.

I've tested to see if i have power/ground to the ECU, and I do. I'm getting power to both pins a11/24 and grounds to a10/a23.

I followed the wire back from when i turn the car to the ON position. I get 12V to the ICM. If i test the ICM A20 wire, heading to the ECU, I get 4.82V.

I am however NOT getting power to my injectors!

So i tested the injector wire from the ECU and no power. Does this mean I have a bad ECU? I popped it open and took a look, it looked pretty pristine - some waxy stuff on the chips was oozing off, but thats about it.

Any ideas?

Thanks~!

 

Have you checked ALL of your grounds, not just the ECU ground?

 

Have you tried to get a code by cranking for 10+ seconds?

 

So far i've check the thermostat housing ground, the two on the fenders, and the fuse box under the left driver side.

And the car used to run fine, no codes (since I changed the dizzy).

 

Put a battery charger or maintainer on the battery and take the belts off. See if that makes a difference.