1uz running rich/ rough

[KLR16V]

my 1uz hilux has decided to run like shit all of a sudden. it hesitates/misses when revving up, feels very sluggish like some of the cylinders aren't getting spark/fuel, and the exhaust is pretty smokey.

the only thing i can think that has made it do this is the heavy rain the last few days has got onto the engine thru my bonnet scoop.

ive checked the spark plugs and some sensors for water and its all dry.

i dont think its the coils, because when i disconnect either one it makes the engine run even worse

Also when i disconnect the air flow meter nothing changes... is that normal?

I dont know what else to do, any ideas?

Also does anyone know a good tuner/ mechanic in sydney that i can take my truck to. im really busy atm and i cant spend heaps of time on it. i think it may just be better to take it somewhere.

cheers for all your help guys

[CrUZida]

Go through and pull one spark plug lead at a time.
It could be that one plug isn't working, or one injector is stuck open.

[KLR16V]

cheers cruzida, i just tried disconnecting injectors and spark plugs one at a time. i had no luck i had spark at all plugs and all injectors seem to be working.

i also cleaned the afm with contact cleaner and that did nothing.


bridging the diagnostic terminals Te1 and E1 at the plug on the engine didnt do anything. maybe the check engine light isnt wired in properly


The hesitation/missing is really bad.
is it running in limp mode? the truck in almost undriveable. it idles ok, but its very hard to get up the rpm.

Its so annoying, i just started uni today and i should be studying, not muking around on an engine lol.

[CrUZida]

Doesn't sound like limp mode.
Normally its either an ignitor or a coil that dies, but you've ruled that out.

Perhaps its something random like your cat, muffler or airfilter has collapsed, blocking the flow of air?

[CrUZida]

Got time to do a compression test? Try and rule out water damage.

[Hack]

I believe air flow meter and contact cleaner = dead air flow meter.

Can you get hold of another to test?

Hack

[dumbass]

check your ecu too
unplug air flow meter and see if it runs better
your coils still might be gone its just at idle they wont break down
but as you put load on them they break down
put a spark plug tester on a lead and increase gap to about 5 or 10 mm
then rev it up see ifu loose spark
i got 2 air flows and 2 ecus depending what model u have

[KLR16V]

i havent taken it for a drive yet with the afm disconnected, but that is the next thing i will test.

As for the coil, does anyone know the resistance range it should have if tested? do i just check between the 2 terminals on plug with small wires.

Also its back firing that bad it pops inside the intake. how much u want for the airflows dumbass?

[dumbass]

they are the older alloy ones
50 bucks plus freight
dont check coils with multimeter as yours sound like thye are working at idle is that correct
best of getting an adjsutable spark tester and check two leads per side one at a time
open gap abit at a time each time u start it and rev it up
u need to test under some load

also check the caps in the ecu

[CrUZida]

I believe air flow meter and contact cleaner = dead air flow meter.

Can you get hold of another to test?

Hack

Not always the case. I've cleaned them before without issues.
Plus, if you unplug and there is no change, chances are its fine.

[dumbass]

I was in nsw last week
Ill be back down there in April if u need it looked at. Heheh
I have wired many a 1uz

[KLR16V]

damn if only this happened last week, could have got u to take a look. pm me ur bank details il send you some money for the coils

[dumbass]

hi
sorry would have been hard to fit it
i flew down wed morning to wire up a car and flew back thursday arvo
i dont have 1uz coils
i have some corolla coils which are same size but im pretty sure the top section where
spark plug lead goes on is a normal slide on to
where the 1uz coils have a smaller internal hole and has a locking tab on the side

coils i have are for your old school just push in type coil lead with no locking tab
but ive heard aftermarket coils are not expensive
but its easy to check if coil fails by increasing plug gap and see how strong the coil is

[KLR16V]

ok Ive got some good news:

I managed to get the truck running much better! (but not 100%).
I cleaned the crank angle sensor which was absolutely covered in shit, and i also cleaned the idle control thingo on the front of the engine.
its not running heaps rich now and idles better. But its still missing and hesitating a bit.

After doing that i cheched the coils using the spark plug gap method dumbass talked about and the spark was strong and consistant.
i Also checked the spark plug lead resistance. and most leads were under 5.0k ohms so they may need replacement.

I also looked at the AFM again, seeing that the truck was running a bit better.
When the AFM is disconnected the engine runs much better, it does hesitate a fair bit tho, like it feels like there is sometimes a 1-2second delay for the engine to respond to the accelerator when its slowly pressed in.... but other than that its good and feel like its got heaps of power.
Does this mean the Afm is stuffed????



there are some pretty good threads on other forums that helped me out. i thought id share them to help others who read this thread with the same issues

this one is for 1uz missing/running bad
http://www.offroadexpress.co.nz/Foru...p?f=47&t=32078

this one if for changing and testing spark plugs
http://planetsoarer.com/penski/ThePenskiFile.html

[dumbass]

if playing with idle motor and stuff helped abit maybe look for an air leak