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Anyone got some ideas what may have caused this? I've put about 50 miles on it up to about 70mph and haven't had any overheating issues. However, it seems kinda sluggish, like maybe it's not aspirating well. Cats?
It may have ingested the fire from a lit cigarette. I don't know why people flip their cigarettes out the window of their car. I use to be a chain smoker, but didn't smoke in my car! You never know.
Any other parts of the air snorkel show heat damage? I suspect that one of the headlight connectors is a heat source and or burning. After market HID or LED headlights installed?
Nope. No evidence of fire or heat damage to the housing. No aftermarket lights or anything external. It's on the MAF side of the filter, aligned with the grate that's covering the engine side of the intake. I didn't get in it with a rag or white gloves, so there could be soot or other deposits.
I haven't touched anything yet, but I'll definitely check that. I'll verify the plug wires are in order. Can I visually inspect for backfire with the air filter and housing off? I was told the water pump was recently replaced by a reputable guy. I saw that the water pump and timing are often done at the same time, so that could be a possibility either plugs or being out of time.
Well, I'm going to pick up a 1991 LS400 with serious electrical issues tomorrow and drive it home about 130 miles. Wish me luck! Sounds like I'll be rebuilding an ECU. I hope it's not melted away.
I haven't touched anything yet, but I'll definitely check that. I'll verify the plug wires are in order. Can I visually inspect for backfire with the air filter and housing off? I was told the water pump was recently replaced by a reputable guy. I saw that the water pump and timing are often done at the same time, so that could be a possibility either plugs or being out of time.
Well, I'm going to pick up a 1991 LS400 with serious electrical issues tomorrow and drive it home about 130 miles. Wish me luck! Sounds like I'll be rebuilding an ECU. I hope it's not melted away.
The water pump replacement needs to remove and install the timing belt. I hope that the guy did it 100% properly. If not done well, the worst scenario is the dead engine.
Usually the engine can be started without the air filter and the housing ahead of it. But you need to attach the MAF and it's housing. Judging from the burnt side of the air filter, I also worry about the MAF. It must had been exposed in the frame and was damaged some.
Regarding the 91 LS400 you are about to re-cap, I hope the board is not seriously damaged by the QAS which becomes very strong alkali at the end of the life and eats copper traces. Damaged boards can't be easily fixed.
The water pump replacement needs to remove and install the timing belt. I hope that the guy did it 100% properly. If not done well, the worst scenario is the dead engine.
Usually the engine can be started without the air filter and the housing ahead of it. But you need to attach the MAF and it's housing. Judging from the burnt side of the air filter, I also worry about the MAF. It must had been exposed in the frame and was damaged some.
Regarding the 91 LS400 you are about to re-cap, I hope the board is not seriously damaged by the QAS which becomes very strong alkali at the end of the life and eats copper traces. Damaged boards can't be easily fixed.
Yeah, is there any way to check the timing aside from looking for backfire?
If that's the case, then I'll be looking for a replacement MAF. Does it hurt it to be unplugged? I've had to unplug and clean the one in my 05 Passat before. I had to drive with it unplugged for a minute because the car wouldn't go.
I've only skimmed the ECU thread. Is it next to impossible to swap out the ECU if that is the case? When I got in the 91(not 92) today nothing electric worked aside from the ignition. Halfway home it killed the battery; either the ECU retards charging or the alternator is dead. After recharging the battery (thanks AutoZone!) I drove another 15 minutes or so and all the lights came on and everything started working, but the car stopped and wouldn't restart. I had left the negative terminal loose and it slipped off! I tightened it back up and was SURPRISED by the improvement in the ride. So I'm hoping I can fix this one back up too. I have a serious problem scrapping good running vehicles.
Last edited by JonnyO78; Oct 10, 2018 at 08:10 PM.
Usually the engine can be started without the air filter and the housing ahead of it. But you need to attach the MAF and it's housing. Judging from the burnt side of the air filter, I also worry about the MAF.
My '91 runs just fine with everything upstream of the throttle body disconnected and removed. So it runs fine with no MAF.
Help! Burnt air filter
