91' FJ80 Starting problem (1 Viewer)

[digital]

I've been troubleshooting an intermittent starting issue on my 91' FJ80 that just started yesterday. The engine just cranks over and doesn't start after I've been driving around. It starts fine when cold. I have to let it sit for about 10 minutes, then it'll start back up.

I followed the troubleshooting steps on jonheld's website (awesome site), when I went to measure the primary coil resistance (+ / -), I got a reading of .001. I get a reading of 12.3k on the secondary coil resistance. Do you think the coil needs replacement? I just want to be sure since the part isn't cheap.

 

[Ali FJ80]

it could be the efi relay which is under the hood. starts cold but once the relay gets too hot it will not restart till it cools down. Mine did this and the new relay from toyota was about $35. Over a year now with no problems.

 

[digital]

it could be the efi relay which is under the hood. starts cold but once the relay gets too hot it will not restart till it cools down. Mine did this and the new relay from toyota was about $35. Over a year now with no problems.

I replaced the efi relay last night, after talking with jonheld, I'm also going to replace the fuel pressure regulator since it too could be failed. Thanks for the reply.

 

[CJF]

I'll bet that takes care of it.

Please let us know either way.

Curtis

 

[TiredIronGRB]

EFI relay for sure.

For anyone else that has this problem...If the check engine light isn't on when cranking, turn the key back to lock and try again, sometimes it will take a few cycles to start.

 

[SteveMondragon]

I have this problem all the time, and it's not the EFI relay either. I have 3 brand new ones from Toyota that I swap from time to time and at any given time, none of them will work so changing them out when they're 'hot' or 'cold' has not worked for me. I even remove and cleaned out the Circuit Opening Relay found in the driver side kick panel fuse block and no luck. Replaced the fuel pump and fuel filter and still same problems. Even replaced the starter because I had one for free.

On a 91-92 (from what I've read in the FSM), there's no Fuel Pump Relay on those years and they have them in 92+. Any suggestions short of replacing the Main Relay or anything else?

 

[TiredIronGRB]

I replaced the EFI relay and it hasn't done it since.

 

[CJF]

EFI relay for sure.

I dunno...

Easiest way to rule that out (assuming the rest of the EFI circuit is up to snuff) is to make sure the CEL is illuminated when the engine is OFF but the key is in the ON position.

After that, hard starts when (engine, not ambient) warm indicates a bad FPR as the prime suspect.

Curtis

 

[digital]

Ok, so here's the deal. I replaced the EFI relay and for over a week the problem has not come back.

I replaced the fuel pressure regulator tonight (per Jonheld) just to be sure and the problem still has not come back. Hopefully this helps the next person searching threads for a fix

 

[thorvald]

between this thread and another I was able to get my 91 running with a minimal amount of time on the vehicle

got a new efi/main relay from Napa and it started right up.

I have a question though, especially as I'm going to be going to Minnesota shortly
Is the relay for sure the bad part or is there a cause to the relay going bad other than years/time spent under the hood?

I plan on getting another for backup but don't want to get stuck in the middle of South Dakota if there's something else I should be checking.

Don't know if it's relevant, but about 5 days ago, we took a road trip and the temp was in the high 90's. When we went out to the cruiser at one point it only clicked-
tapping the starter got it going and no problem with the starter since.

thanks

this place is great paired with a fsm

 

[DaveFJ80]

Been there, done that and worked on it for 4 months straight. EFI relay was the first thing I checked, and that helped initially, but that obviously didn't help my overall problem. My truck would not start after running every now & then when it was hot. I changed everything everyone else already listed above and even more.

Bottom line was, it was the distributor that needed to be replaced. Made sense since on a previous 91 Honda car I used to have, usually the ignitor was the culprit with the same symptoms (when it's hot, it won't start but it fires up just fine when it's cooled down). But I replaced the external ignitor & coil on my truck and still had starting issues. Later we diagnosed that it was the distributor internals so I got a new distributor. Since then, zero problem with staring the truck up, regardless how often I drove it. And it's been fine now for the past 3 months and I couldn't have been happier.

 

[thorvald]

I guess I should have added that today it didn't start after sitting all night and it turned over, just wouldn't catch. I was thinking fuel related or something until I started searching.

Was the first time I've had the problem of turning over and not starting with the '91. I replaced the starter a year or two ago with a remanufactured one.

 

[jonheld]

I guess I should have added that today it didn't start after sitting all night and it turned over, just wouldn't catch. I was thinking fuel related or something until I started searching.

Was the first time I've had the problem of turning over and not starting with the '91. I replaced the starter a year or two ago with a remanufactured one.

First keep in mind that the starter (cranking the motor) and EFI (ECU and spark) are 2 different circuits. You should verify if you have spark while cranking. If spark and no start = no fuel.

I compiled a diagnostic procedure on the EFI circuit on my website. Have a looksee.