running rich/black smoke

[v8ln106]

Hi guys ive just put my 1uz in my hilux and got it all wired up. i replaced the plugs. the motor idles bad with black some and if i turn it off it doesn't start again i have to take the fuel pump fuse out and turn it over with the throttle half open and it fires after about 5 seconds, and today when i started it up i let it idle for about 10 min then i open the throttle right up it revved up but when the revs came down it died. any ideas why this is?

Thanks

 

[XR8tt]

Yes its over fueling.. Check TPS, maf and fuel reg...
Then check injectors.. 02 sensers...
Could be leaking diaphram in fuel reg ??
Earthed out injector on 100 % cycle ???

 

[gloverman]

recheck the wiring. We are seeing lots of stuffed air flow meters these days. Also check there is 12 volts at the B+ terminal in the daignostic box on the motor. cheers

 

[v8ln106]

i just put a new fuel pressure regulator in as i broke the last one. and i have adjusted the TPS. there is a small hole in my exhaust and fuel is dripping out of it when the motor is running. i have to take the fuel pump fuse out and turn the motor over about 6 times to get it going and even then it only starts on 3 cylinders at the most. its got me stumped because before i put the new plugs in and the fuel pressure regulator it was running fine although it did have a high idle that surged?

Any help would be most appreciated.
Thanks

 

[v8ln106]

also there is 12 volts at the B+ terminal in the diagnostic box

 

[gloverman]

Start at the beginning - Compression test - check all leads , Check coils - I have insulated pliers and I lift each coil lead out of the distributor tower and watch the spark. You can do the same with the leads. Check firing order - easy to get wrong , check cam timing. Check fuel flow and pressure. Check fuel is clean petrol (no water or diesel) Unplug air flow meter - should still run but noticably different. Listen to each injector and check they are all clicking. Then I get out my scope and check signal. Cheers

 

[v8ln106]

I think it is the 02 sensors, i will take them out and have a look at them tomorrow. i haven't taken any of the leads off at the dizzy caps so it cant be firing order and it revs out fine it just floods its self when the revs drop back down. so i don't think its a spark issue. could be injectors i think that they might be on 100% duty cycle as it has fuel dripping out a small hole at the end of the headers.

 

[gloverman]

Maybe try unplugging the cold start injector if it is an early motor too.

 

[sideshow]

a 1uz which i wired 3 years ag started playing up
the ecu was turning on one pair of injectors all the time full open
so i sent him ecu today see if that will fix it

when u unplug ecu injecotrs turn off
so its inside ecu i guess
maybe u have similar prob
get a noid light and see which inejcotrs are overfuelling
o2s wont make it overfuel
bad o2s should not even make it run very rich as ecu should compensate for them
if motor ran good before u wired it then i guess its yr wiring

 

[DNTOEARTHMAN]

Club Lexus

Hi guys ive just put my 1uz in my hilux and got it all wired up. i replaced the plugs. the motor idles bad with black some and if i turn it off it doesn't start again i have to take the fuel pump fuse out and turn it over with the throttle half open and it fires after about 5 seconds, and today when i started it up i let it idle for about 10 min then i open the throttle right up it revved up but when the revs came down it died. any ideas why this is?

Thanks

There is a thread there, try ECU temp sensor, you have poor gas milage as well?

 

[sideshow]

same thing goes
i doubt the coolant temp sender would make it poor fuel out the exhaust
as the std ecu has soooo many fail safes
u need to find which cylinder is pooring in extra fuel

 

[sideshow]

find the o2 signal wires and check if voltage is around 0.5 volts

then check coolant temp wire voltage should be bout 1 volt hot and 4 volts cold

 

[v8ln106]

I think all cylinders are over fueling? it back fired out the intake about 3 times yesterday when i got it started, maybe all injectors are at 100% duty cycle? i dont know its got me stumped.

 

[XR8tt]

Check if one side of injector wire / plug is active and the other wire negative - should pulse.. You'll need a LED test lamp or noid to check...
The negative side maybe connected or shorted to earth ????
It's often the SIMPLE things you overlook when diagnosing these things !!!!

 

[sideshow]

if all injectors are overfuelling u have ecu issues
very rare for all to be shorted to ground
very rare for any to be shorted to ground unless wiring was done wrong
and if the injector wiring wa sshorted to ground id assume alot of other wires would be shorted too

to me seems like ecu prob if wiring was done right
have u checked to see if injectors are working
ecu might send the signals but injectors might be stuck and dribbling fuel out
or yr airflow might be faulty

 

[XR8tt]

As said start from injector and work your way back to ECU...
Disc air meter and fuel reg. Check if there's any fuel entering manifold through fuel reg manifold hose...
Disc cold start if it has one....
Check fuel pressure ...

 

[v8ln106]

well i replaced the air flow meter i went average, but was still choking between 1000-3000/4000rpm(not sure no tacho at the moment) so i check the ecu it spat out to codes 21? not sure may have been 22 and 41 any way it was engine coolant temp and throttle position sensor, i had wired in an after market temp gauge, it must have been reducing the signal to the computer as i used the same sender, so the cold start injector never turned off.

Thanks for all your help guys sorry I've been abit slack with checking the post updates