J-Roc

Thanks guys, I believe it was the fuel pump relay. I warmed the engine and it seems as if the relay got some heat soak and began acting up. When the no start was duplicated, the relay was taken out and jumped with a paper clip. The engine fired back up, so I replaced the relay and its been good so far! We'll see how goes it Thanks again all!!!

Leadfoot, would these values still hold if the car were at normal operating temps or would they be different?

Austin, would your car start when it was hot? Can someone explain to me in detail how a broken harmonic balancer could keep the engine from starting? Mine starts fine when cold, but fails to restart when hot :( w/no check engine light (weird)

Very interesting! So when it cooled off, the car would start again? About how much didja pay for a new balancer? Am I correct to say that if one of the cam sensors were faulty, the car would still run on 4 cylinders? or???

Hi all, I've got a no restart situation when my 91 LS400 warms up. No engine codes are present, but I'm still going to check the ohm values for the cam and crank sensors as stated in another thread. My question is would a slipping harmonic balancer cause a no restart situation??

Hard to say on the cost of just doing the balancer itself, as I did the TB etc, at the same time. If your guy replaced the sensor that mounts by the balancer, they should have been able to look to see if it was slipping or not. You need to pull a lot of stuff away to get to the piont that you can see it. Then try to turn the balancer and see if it slips. Let me get this right...So if the harmonic balancer is slipping, the car will crank but not start? I am also experiencing these symptoms on my 91...When it gets hot, it will fail to restart... 'Check engine light' does not come on when the car fails to restart...I'm getting spark and fuel...

Just an update...the problem was fixed!!! :chairshot: Drivers side coil went out It idled smooth, but it felt like it was running on 4 cyl (it actually was! ) Since it had 2 dizzys and no trouble codes thrown, I had a bear of a time trying to diagnose it (I've grown accustomed to the 1 dizzy) I was very surprised that the code for a misfire wasnt thrown...Then again we're talkin about the basic OBD. Anyways, now it runs like a top, especially after the extensive cleaning/replacement of all the worn parts. Hopefully the trans can handle the new power lol Thanks you all for your help!

Can you elaborate more on the "four cylinder setting?" How does one go about accomplishing this? Also, if the timing is off, how do you adjust it? I know its not like an American V8 where you just unloosen the dizzy and turn it accordingly...Thanks!

Well, I deduced that since the car performed the same when the exhaust was "unhooked" as opposed to it being hooked up, it could not be a plugged exhaust system. I wish it really was!!! :chairshot: If the computer was malfunctioning, wouldnt it throw an engine code? Anyone know how to reset/check timing on this thing??? Thanks!

Yep, the glowing cats heating up the oily undercarraige to SMOKE and the lack of power prompted all the parts being replaced. The parts were all original and worn. I have no idea how the engine even started, let alone ran lol. It idles just fine at about 650 rpms.It only put put puts when you stomp on the go pedal...Doesnt really go anywhere. I cleaned te MAF sensor out, still the same...Like I said before, I drove down the streets with the exhaust "unhooked" and it still felt sluggish. The new plugs have no more than 5 miles on them...Good points all, so how do I go about checking the timing? I have the gun, but the 2 dizzys are new to me...

New cats could be faulty?! No way, I checked them before i welded them back in! I'm thinking its running WAAAY too rich because all the signs point to it...Fouled plugs, glowing *NEW* catalytic converters, fuelly smell from exhaust, feels like its choking upon acceleration...Soo, with that said- what do you guys think it could be? There are no engine codes thrown ;[ Dirty MAF? Faulty 02 sensors (even though there are no codes thrown)?? I'm runnin out of options fast! lol Thanks again for all the pointers guys!!!!

Wouldnt a faulty MAF sensor throw a code? Should I just clean it out with electrical cleaner? What would cause an EXTREMELY rich mix? Would faulty 02 sensors throw a code? When I took off the catalytic converters to replace them, I test drove it down the street and it still felt sluggish...

Yeah, all plugs were fouled when inspected...Idle is smooth, just no power...put-put-put...

Hi all, My friend has 91 LS400 w/the 4.0 V8 w/180k and we can't figure this one out :cries: The symptoms are no engine codes thrown, lack of low end power, and the cats are glowing to the point of burning the excess oil and the engine bay is smoking ALOT! Also, acceleration from a stop results in a "put-put-put" sound from the exhaust. I've changed caps/rotors, spark plugs, spark plug wires, new, air filter, pcv valve, cleaned out TB, cleaned out EGR valve, replaced cats. The pickup is better, but the cats are still glowing when the engine is revved. What else can I do? Check timing? :( Any pointers are greatly appreciated! Thanks all...

How do you check/adjust the timing on these engines? Thanks!