98 Civic cranks but won't start
 

I'm trying to help my son out with his 98 Civic. We just rebuilt the engine, and now we can't seem to get it to start and run. It does crank over, so nothing is "locked up". So far we picked up a spare main relay, just to be safe, as we hadn't checked the old one yet, and on the forums, every bodies first reply is that it's the main relay. Well it's not. I checked the replacement before I lost daylight last night (my son works nights, so he sleeps during the day). However, we seem to have limited power going to it (at least that's how it appears to me). I say that, as some stuff has power and some doesn't. When we re-installed the engine, everything wired up like it was supposed to, ran in the same channels and the car did run abit on 3 cylinders (spun #4 rod bearing) before the engine got pulled. Now 7 or 8 months later, we're trying to get this up and running again (had to gather the money, then parts to rebuild first). I don't have a 98 Civic Service manual, so I'm blind here, so any help that can be offered is willingly accepted.
We are going to double check for spark, and look in the daylight to see if there are any blown fuses leading to the main relay. If I use my test light on the main relay, I can get the pump to run, which is throwing me off. Without probing, the pump doesn't run, hence I'm thinking blown fuse. Another thing, I tried hooking up my code scanner to it, to see if I could any codes, but I'm getting nothing out of the data port (like no ECU signal).
Any help is appreciated. I know I should be asking on a Civic forum, but I'm an Accord owner. :D

OK, we finally got a chance to test for spark again, and found none. Also tested all of the fuses (inside and out) and found none to be blown (used an ohm meter to test them). Seems like the ECU and a couple of other things aren't powering up. When you turn the key to position II, half the dash lights up, but no CEL, seat belt warning, and some others don't light up. In fact the hand brake light flashes at you, until you set it back to off (no hand brake on position). At this point I have no idea what's going on, or why nothing is working. We did remove and clean all of the grounds in the engine bay, if nothing else to make sure they're clean.

He' almost at the point of removing the engine and trans again, and doing a K-20 swap, since he knows it'll need to be re-wired and need to have the ECU changed. I said to him IF he could get me a copy of the fuel system for his Civic, I could do a "pin out" test of the ECU to make sure everything is connected under the hood. I had to do that when I was working on my 97 Accord, before I fixed it.

maybe this will help

https://www.clubcivic.com/forum/thre.../#post-3454408

https://www.d-series.org/forums/forc...d-p28-ecu.html

Only half the dash lights up? Check whether the wiring plugs at the instrument cluster are loose or flaky.

Fuses good with ohm-meter? How about loose contacts where the fuse plugs in? Check whether the fuse has voltage when it's installed in the fuse box?

Without a wiring drawing, I'll put out a guess about one of the big screw-in fuses in the engine compartment? Those cover a number of individual small fuses so that might explain several things being out. I'm assuming the Civic has a similar arrangement of those big fuses like the Accords.

Thanks for the links, but they are for an OBD1 car, and this thing is OBDII. I guess I'm going to have to back probe the ECU. I found a list of the pin outs for OBDII there. Just wish I had the rest of the list showing which are voltage, and which are ohm readings. That was how I found my 97 Accord's issue.

Yes Jim, it does use some of those same "bolt on" fuses found in Accords. I was kind of hoping the 2 cars were more similar, but I guess not. I do have FSM's for both the 94-97, and the 98-01 Accords. The pin outs are definitely different though, even between them.
That's why I say I'm blind here, not having the wiring diagram, or the outputs that you "should" have (what the ECU is looking for). Those are only found in the FSM.

Absolutely, OBDII started in 1996. But maybe your problem, if it does turn out to be the ECU, is a bad capacitor(s). The links weren't intended to be specific to your model year.

Hope you resolve the issue. Keep us posted.

Over the weekend, I did get to do a "pin out" test, as my son picked up a FSM for the car. Found we weren't getting a good ground thru both LG1, LG2, PG1 and PG2. These all good to the thermostat housing for ground (G101). While the connection was clean and tight, the wires were broke in the plastic sleeve about 2-3 inches back inside it. Fixed that, but still no run.We also replaced the CEL bulb, and got the MIL indicator to light up (why we had no CEL light). Swapped out the ECM/PCM with a "known good one" like the book says, and it fired right up. So it was actually a combination of problems. However, the car is still laid up due the alt seizing (bearing locked up). That's getting dropped off at a rebuilder I know later today, since it's supposed to be a 150 amp unit.

Well, 2 steps forward, 1 step back. The rebuilder closed the doors of the shop and went out of business. Sucks as I had other work I was going to send. Ended going to Advanced and got a CarQuest rebuilt alternator (they had a stock 1 in stock) after talking with my son, since it's his car. We'll probably install it Friday afternoon, so we can let everything do a "re-learn". Then he can work on rust repair work (wheel well lips).