sbman
Supporting Vendor
A few weeks ago, while off road in Anza Borrego, my 1997 FZJ 80 failed to start after short stop. It cranked ok, fired and then coughed and died. Subsequently cranking it produced no firing at all, just cranking away from the starter. After 30-40 seconds of additional cranking it did finally start and ran basically normally.
It didn't do it again for a bit, but then started doing it intermittently. Intermittently became frequently as in every time I shut it down for a few minutes and didn't let it cool all the way down, it would fire, cough and then require tons of cranking to get it to restart. When it was doing this it would also smell strongly of fuel and white fuel vapor would come out of the tail pipe. It was pretty obvious that it was flooding but the cause of the flooding was unknown. No codes thrown. Three possibilities that I could think of:
Then I disabled the evap system and things seemed to improve. No hot start issue for a couple of weeks.
Then it started doing the hot start thing again and I also started noticing intermittent transmission issues (torque converter lockup not engaging or engaging on and off while cruising on the freeway, shifting into/out of overdrive for no reason on it's own), occasional pinging on steep grades under throttle, and high idle (1500-2000 RPM), also intermittent.
After a week or so of this, it finally threw a code, coolant temp sensor. It took almost 5 weeks and 3000 miles to throw this code. I put the scan tool back on and kept it on for a few days while driving around and the EFI coolant temp sensor would function normally part of the time reporting realistic temps, and then shift 100-140 degrees lower than reality at random times.
Replacement of the sensor has fixed all of the aforementioned issues. the sensor actually had a crack between the connector and the body of the sensor.
Posting this for anyone else that might be having similar issues. A coolant temp sensor failure can be intermittent and the EFI system is really bad about throwing the code, not caring that the temp is being reported as 190,190,190,45,45,45,190,190. Also, it is easy to chase down red herrings when things are intermittent, it can seem like an unrelated change made an improvement.
As a result of this I did replace the brake booster hose (original), evap canister hoses (also original) and the intake hose (also original) to prevent any upcoming intake leaks. All of these lines were very hard and brittle, just waiting to crack open.
It didn't do it again for a bit, but then started doing it intermittently. Intermittently became frequently as in every time I shut it down for a few minutes and didn't let it cool all the way down, it would fire, cough and then require tons of cranking to get it to restart. When it was doing this it would also smell strongly of fuel and white fuel vapor would come out of the tail pipe. It was pretty obvious that it was flooding but the cause of the flooding was unknown. No codes thrown. Three possibilities that I could think of:
- Injector leaking into manifold
- Evap system stuck open venting into manifold
- Coolant temp sensor failure causing EFI to initiate 'cold start' into hot engine
Then I disabled the evap system and things seemed to improve. No hot start issue for a couple of weeks.
Then it started doing the hot start thing again and I also started noticing intermittent transmission issues (torque converter lockup not engaging or engaging on and off while cruising on the freeway, shifting into/out of overdrive for no reason on it's own), occasional pinging on steep grades under throttle, and high idle (1500-2000 RPM), also intermittent.
After a week or so of this, it finally threw a code, coolant temp sensor. It took almost 5 weeks and 3000 miles to throw this code. I put the scan tool back on and kept it on for a few days while driving around and the EFI coolant temp sensor would function normally part of the time reporting realistic temps, and then shift 100-140 degrees lower than reality at random times.
Replacement of the sensor has fixed all of the aforementioned issues. the sensor actually had a crack between the connector and the body of the sensor.
Posting this for anyone else that might be having similar issues. A coolant temp sensor failure can be intermittent and the EFI system is really bad about throwing the code, not caring that the temp is being reported as 190,190,190,45,45,45,190,190. Also, it is easy to chase down red herrings when things are intermittent, it can seem like an unrelated change made an improvement.
As a result of this I did replace the brake booster hose (original), evap canister hoses (also original) and the intake hose (also original) to prevent any upcoming intake leaks. All of these lines were very hard and brittle, just waiting to crack open.
