Experts,

I just bought a 1990 Accord with 157k on it that the previous owner said was "stuck in sports mode". He had mangled the sport mode button and just twisted the two wires that go up into the shifter **** together and when I un-twisted them the "S' light went off. It does seem to shift at high revs but does go into 4th gear, so after reading a bunch of threads here and elsewhere I decided to take a look at the lockup and shift control solenoid valves since it seemed easy and safe. What could possibly go wrong?

I unbolted the aforementioned solenoids and, finding the screens and transmission-facing sides unclogged and healthy looking I bolted them back on.

Like a fool I decided to do two things at once and also disconnected the negative battery cable for about a minute.

When I hopped in to back it further into the garage, it would no longer start. It turns over strong, but won't catch. If it were no fuel I think it would sputter a little wouldn't it? It sounds like my old pickup did when it blew the EFI fuse once.

The 10a fuse labeled ECU under the hood appears undamaged. All I have is a crappy test light but I could not get it to light up by touching it to either side of the fuse. The light does light up when touched to the battery terninals. I don't know when power should be going through this fuse (all the time?) so I left it alone.

Sticking my head up under the driver's side dash, I could hear clicks coming from (at least nearby) 3 black relays up there. This is when I turn the key just beyond II but not quite at cranking the starter over.

I have yet to pull the ECU or TCU or whatever it is in the passenger side firewall/floor. There seems to be 2 windows where LEDs might light up & provide a flash code but none do in either, unless they are too dim for me to see.

The CEL stays solid. When I was looking for codes by jumpering the blue service port under the passenger side dash it used to go on for a few seconds and go off.

I removed the least stuck-and oil-puddled spark plug (2nd from left) and let it sit on the valve cover, connected to the wire, while I cranked the engine. I am alone, and couldn't see all that great through the windshield and under the edge of the hood, but I really don't think there was a spark.

I read somewhere to check the ground under the thermostat housing but this is either long gone or was never there. I suspect it was moved, but I don't know where it would come from to check where it might have been moved to. I figured that was the culprit since I had been jamming my hands down there to pull the solenoids, but there's nothing hanging loose around there, nor a broken connector bolted to the housing or frame.


So - any idea what the heck I did to this poor old thing? Hard to imagine the loss of a little ATF could cause it, and it sure seems electrical. Could I have possibly blown the computer or an electrical component? I don't have a multimeter but perhaps it's time to invest.

Thanks for any insight and diagnostic help.

Rob

 

I would reset the engine and transmission computer by removing the 7.5 amp backup/radio fuse in the engine bay fuse box.

Volt meters are $10 at places like Wal-Mart. For most electrical testing on a car, you need to test for voltage and resistance.

 

Thanks for the fast reply! I didn't realize you had, and went out there again after looking around some more online. I tried pulling the 7.5a Backup/Radio fuse and cranking with it removed and then put back in. No change.

Does the ECU have a fuse right on it?

Are both the ECU and TCU on the passenger floor next to each other under the metal plate on a 90 Accord?

Am I wasting my time focusing on the ECU when I should be looking for instructions to test the coil or something else once I go get a multimeter?

Does my description of the clicks under the driver's dash sound like the main relay is OK?

 

Turn keyswitch to On. You should hear a couple clicks under the dash and fuel pump buzz fro 2-3 secs and go off. Check Ehgine Light (CEL) should go off w/ the fuel pump. If you don't hear these you likely have a fuel supply problem.

If you have a timing light, attach to one spark plug lead and turn engine over while observing timing light. No flash means no spark is occurring in cylnder.

If you don't have a timing light, try removing intake air duct and spraying starter fluid or throttle body cleaner for 4-5 secs, and then attempt to start. If it doesn't try to start, no spark is highly likely.

If no spark is confirmed, first step is to check blk/yel wire at distributor connector for 12V. If no voltage keyswitch assy is likely fault. If voltage is present, then distributor fault; coil or ignitor. See DIY forum for tests of coil and ignitor.

good luck

 

I don't think I'm hearing the clicks or the fuel pump. I only hear clicks when I turn the key just past II but not to start. I'm pretty sure I don't hear the fuel pump at all. The beeping has been distracting me. I never noticed the clicking and whirring before I screwed it up.

Gonna go out and spray some starting fluid in and see what happens.

Perhaps I blew a shaky main relay by removing/reattaching the battery.

 

If engine kicks over w/ starting fluid, then spark is likely OK and fuel supply seems likely.

Suggest getting someone to listen w/ gas cap off for fuel pump to come on. If no pump sound, then no fuel supply, no start.

good luck

 

It's getting weirder. Maybe better.
It sputtered when I sprayed some starting fluid in and there was no clicking or whirring, so I stuck my head under the driver's dash again and poked around, hoping the main relay would make itself obvious. It did not but I saw a few possibles and was just about to head in and try to find out what it looks like/where it is.

I figured I'd listen a little closer to make sure, and miracle of miracles I heard the fuel pump! I turned it over and it started up - real rough - I guess from the starting fluid, but few tries got it running as before.

I took it around the block and I think the tranny was behaving a teeny bit better. I backed it back in and futzed around listening for the fuel pump and the clicks when that stuff stopped, the CEL stayed on solid. A few more tries and it started and immediately stopped or just cranked over.

I jumpered the service port and the S light gave me a code! Multiple codes I guess. Looks to me to be 1, 2, 7 and 8. I'm going to go look them up now. CEL stays solid. What the heck? (rhetorical)

 

The MFR in the 90 Accord is difficult to see. It's up high against underside of the dash near the outside of the body. If you have cruise control, you may need to move the cruise control out of the way to see the MFR.

Do you have a manual? If not, suggest you download the 91 Accord Manual from Online Manuals links in DIY forum. It will help you locate the MFR.

good luck

 

Yeah I found it, I think. It's a black plastic box about 1"x2"x2.5" with a jack about the same shape as a phone's but 2 or 3 times as big. Way up under the driver's side dashboard toward the left of the car. Couldn't unbolt it but saw a youtube vid on taking the guts out and that's what I did. The circuit board looks fine. The car is starting reliably now. Oy. Maybe it was the heat and I just can't see the problem on the MFR.

Should I ask you guys about the transmission issues I got from the S codes or start another thread?

 

BTW - online down-loadable manuals?! That is great. This place is awesome. Thanks very much to everybody who helps out here.