HovX

Hello everyone!

I am a new member on honda-tech!

First I want to say thank you to everyone on here (and other honda sites as well) as you guys have helped me learn quite a bit about hondas over the years. I have helped on about four different swaps over the years and the information I have found made all of that possible! By no means am I anywhere near knowing everything there is to know about hondas (or cars in general), but I know my way (mostly) around an engine bay.

Anywho I am in a bit of a bind and need some advice.

Last year I bought a running 1988 CRX HF from a friend of mine for about $500. It was blowing a bit of smoke when starting from a stop. It still got up and had as much go to it as you could expect an HF to have. My friend doesn't know much about cars passed filling up tires with air and changing his own oil. I drove the car home and cleaned it. Threw it in the shed for about 9 months while I gathered what I needed to do a swap. Originally I was going to do a Z6 swap. But after buying a bare Z6 block for about $50, I found a D16A6 for about $200 and snatched that up. It came with the harness, distributor, intake, exhaust, and pretty much everything else except the trans and alternator. I picked up a trans and just used the alternator from my HF. I changed most of the gaskets and put a new timing belt, water pump, tensioner and spring, and alternator belt (the car doesn't have AC) and put a new thermostat and O ring in.

Put the engine in everything went smooth. Picked up an ECU for it. I also put on a cold air intake, and an aftermarket 4-2-1 exhaust header. A previous owner put a two inch cat back on the car, and I picked up a high flow cat as well. The cat will need to be welded on, and the headers don't quite reach the cat on the car. So it is running open down pipe with about a two inch gap before the cat. I'll get it welded up soon as I can get the car driveable (I know this is the stock forum, but everything else is stock, I promise!)

Now here is where the problems are coming in.

Upon start up the car has no CEL but idles at about 3000 rpm and then slowly drops to about 2500 and holds steady. After maybe 3 or 4 minutes of idling the car goes slightly up to maybe 2700 rpms and holds steady. Not even a single cough or sputter. Revs quickly (I may or may not have put in a light weight fly wheel...Okay I did). Note that all idling speeds I mentioned have been with the clutch engaged. The rpms do rise a little when I press in the clutch.

I attempted to time the engine and the timing mark was way off (towards the fire wall). I moved the distributor all the way forward (towards the radiator) and it brought the mark closer to lining up with the plastic V on the timing belt cover. But even with the distributor all the way forward the timing mark was still about 3/8th-7/16ths too far towards the fire wall. I bolted the distributor up all the way forward because might as well get it as close to in time as possible. I believe I may be off a tooth with the cam timing, however I want to get the idling issue sorted out before I mess with that as I read online that the engine should be idling around 700-800 rpms for timing. And yes I did jump the connector before timing the engine.

Next thing I tried was I unjumped the plug, pulled off the IACV and restarted the car. Idle dropped to about 1100 rpms and surges back to 1500 rpms constantly and the CEL came on as it should. Almost like someone is constantly blipping the throttle. The temp gauge went a little crazy. Sputtered up and down before going into the red at the top of the gauge. I shut the engine off. I let the engine sit to cool down. After about 10 minutes it was cool enough to open the cap without an issue and the upper rad hose was easy to squeeze. I never saw the fan kick on either (Note I have had the engine running on and off for a few minutes at a time for roughly half an hour, it should of been warm enough for the fan to turn on at least once, especially if the temp really was in the red). I tried to bleed the coolant (the car is on jack stands and the rad cap is the highest point so I just left that off) let the idle surge for a few minutes and saw no bubbles come from the coolant. Shut the engine off and plugged the IACV back in but left the rad cap off. Turned the engine on and the idle shot back up to 3000 rpms and dropped back to 2500 rpms like before. Finally the first clue towards fixing the issue. However, still no bubbles. Started adding more coolant and and it started gushing out (obviously since the car was idling so high). Then the gushing stopped. I added more coolant, and went into the driver seat to see if anything was up. Temp gauge was still in the red. But then more coolant came gushing out like a geyser and my temp gauge went all the way back down. The gushing stopped and the coolant gauge jumped a few times before going back to the red. The fan still wasn't going (I hope it isn't bad, haven't tested it but it worked fine when the HF engine was still in).

I did spray a few points I thought could be vacuum leaks with carb cleaner, and nothing changed. I "misted" the engine with carb cleaner and nothing changed. But there are still more places to check.

I haven't touched the idle screw due to the fact there was some gunk in where the flat head would go. Sprayed cleaner in in there, hopefully I can get it to move.

I am using the HF harness with the EGR plug just hanging there (no where for it to go now).

Fresh oil was put in before the first start with a good amount of cranking before the first start to build oil pressure.

I did not try to time the engine with the IACV unplugged.

Sorry for such a long post, but I wanted to give as much of an account of what I have done to the engine as possible to help diagnose the issue. Any feed back is welcome. I have tried searching all day and found bits of pieces of information, but most of it hasn't helped which is why I am making this post. If any more information is required please let me know! I have been waiting for the engine to cool down after the coolant geyser and am now going to try and switch the IACV from the HF engine to the SI engine and see what happens.

Also the CEL doesn't come on after the IACV is plugged back in, so as far as I know the ECU isn't sensing anything else wrong.

Thanks again for helping out a ton over the years and also thanks in advance for your replies.