No accelaration,,fuel smell,,,blah.blah.blah

[bm1139]

It seems to be a pretty common fault with a aging 1uz...but gentlemen, i need some opinion in pin-pointing or diagnosing MY particular problem as lexus standard mechanics, diagnostic tools and spare-parts are hard to come by in my vicinity...

no cel shown..
strong smell of un-burned fuel
glowing cat....well i have gutted it.
idling seems to be ok until shift into gear...idling speed got even worse with air-con turn-on.
extremely high fuel consumption ......1.5km/ltr....
no acceleration..naturally..
able to rev when in neutral but sounded slugging not as instantaneously.

i have changed the spark plugs,air filter,fuel filter,clean maf and throttle body but to no avail..as my is a 93 ls400 (obd1) a faulty maf,o2 sensor would throw a code would it?i am contemplating on 1)changing the coils 2)check cam timing..any second opinions??please......

 

[Peewee]

Check for spark coming from both coils.
If both coils are sparking, then I'd be looking at a couple of severely leaking injectors (highly unlikely though)

 

[bm1139]

forgot to list that i have in fact had the injectors cleaned and check for leaks while having the throttle body cleaned.i have too checked on the igniter (unpluging anyone of them would cause the engine to stall immediately)Sir kindly please elaborate on inspecting the coils.thanks

 

[bundymonkey]

Mine is suffering the same problems did you get to the bottom of this as I have just recently replaced the leads and plugs and I am scratching my head as to what the problem could be

 

[gloverman]

The best way to check the coils is remove the LH spark plug cover (the one with the writing on it) and take #7 and #5 plug leads out - they are both run by different coils. Get some old spark plugs (or spark tester as we have) and open the gap, earth the body of the plugs against the manifold and start the engine. If one doesn't have spark then trace the leads back. We have an import motor that went into a jetboat - it had two stuffed coils - idled perfect, started well but didn't make enough power.
The reason unpluging the ignitors (or coils for that matter) is the ECU receives a feedback loop to show spark signal is present - if it doesn't get that signal it shuts off the fuel. We change enough coils on customers cars we keep them in stock - and I am not a lexus dealer - just a small workshop - good luck cheers

 

[bundymonkey]

THanks will give that a go this arvo

 

[ricmeu]

uzz32 i bought died after 20 k's,with this fault

hi, i bought it and about 15 mins after driving it, produced the fault you seem to be telling me. 1. changed plugs, no fix. 2 found that a lead had been pierced by the rocker cover screw, which subsequently wrecked the coil. PLUGS LEADS and Coil Should fix.

 

[bm1139]

thanks guys for the inputs but the problems still's there..even after changing the coils n leads....n more bad news guys.....i'm getting bald after all the scratching.....mmmmmm

 

[bundymonkey]

mine ended up being the fuel pumps