I have searched the posts and cant find an answer for this.

I bought a 93 Prelude real cheap(< than 200) but the PO threw a rod, so I bought a new engine from JDM Engine Depot. Old engine was a H23A1 and the new Engine is a H23A3. I dropped it in, swapped the Dist., fuel rail, and intake manifold. I have hooked everything up(I think) and no start. It cranks but the fuel pump doesn't turn on, and no spark(i think). I by-passed the fuel pump(hooked it to power to make sure it works--it does), still nothing. Another thing I noticed is the fuel gauge and temp gauge are real dim. seems to me they should work correctly. I am new to import engines(well computer controlled engine actually) as I have rebuilt a few Ford 302's and such. So where do I start? would a missing knock sensor cause this as I wasn't going to spend $100 bucks on a new one if I can help it.

Thanks for your help.
Dan in Jupiter--AKA Sprout

 

knock sensor can be bought for about 20 buck on ebay..
u should also dl the helms manual.. it would help trouble shoot..

 

Check main relay, not sure where it is on yours but most are under the dash

 

Ok I will check the relay.

 

Checked the relay-- is good, am thinking its the ECU, as the relay doesnt get a ground from the ECU to turn on the relay coil for the fuel pump. when I ground that wire on the relay the pump turns on. more troubleshooting ahead.

 

OK i have been had. I just "checked" the ECU and it seems like the PO swapped it out with a bad one. All the bolts and so forth were gone and it was just stuck under the carpet. No wonder I got such a good deal on the car. Should I go to ebay or just spend the $200 or so and get a reman one?

 

Ebay, or check the classifieds on here, you are looking for an OBD1 P14 ECU.

 

Ooops ... I thought I had one ... mine's a P12

Another option is a chipped ECU if you plan on building it later

 

Ok its been awhile, but got a ecu on ebay(30 bucks), didnt fix the problem. did some more troubleshooting, found the ground wire going to the fuel pump relay was bad(the ground wire itself not the connector). Car started right up. now I have another issue, the fuel and temp gauges are very dim and go out when i turn on the lights. Any Ideas?

Dan in Jupiter

 

Those have a habit of going out. Mine started fading out while I was driving and within 5 minutes they were gone. I bought new gauges and that settled that.

But your issue maybe something else. Make sure they are connected well. You'll have to take the long plastic piece off under the top of the dash (should be ~10 screws), tweeter covers, and go from there to get behind the gauges.

It could also be cracked soldering points on the board for the gauges. You'll have to take the white plastic back off the pod to get to the board. Be careful not to strip the screws because they can sometimes be hard to unscrew if they haven't ever been broken loose, and a striped screw just ruins anybody's day.

 

I think it might be something else, as I also noticed that the brake,door,trunk and brake light warning lights are on even though the doors and trunk were closed and e-brake off. I think I have more bad grounds or connections. got to run down those gremlins. At least it runs nice.

Dan in Jupiter

 

Could be bad grounds but i've known for that gas/temp gauge to **** out. I've had one that the gas/temp would not show up when i started it then like 15-20 mins down the road they'd just pop back on. So i replaced that one.....and now this new one is doing the same thing. Except opposite it comes on at first then goes out. lol I had to re solder my whole climate control so lights and defrost would work i think i might try it this time around with those gauges.

 

I'll see if I can pull the board out tomorrow and reflow all the solder on it. I'll bet its a cold solder joint somewhere thats messing with the gauges and idiot lights.

Dan in Jupiter

 

Had the connections to the lights in that panel crack at the solder joints. There is a ribbon style cable that connects those lights to the main board. Once you get that middle section of the dash out and take it apart you should see what I'm talking about.
GL
Mike