13-BT Rough Idle

[A2B in a TLC]

Hi gang,

My 1988 BJ74 now has 166,000 km on it. Starts in a split second, even in sub zero C Vancouver winter.

At about 120,000, I had the injectors serviced (rebuilt).

It used to spew the black in the hills until a few months ago when James B and I shimmed the waste gate on the turbo. We turned up the boost to a max 11 lbs. but did not touch the fuel.

Now, even with pedal to the metal on a long hill, its tough to see smoke.

I am generally really happy with her. Did 25 mpg imp on my way back from 100 Mile House on the weekend. Tranny is an A440.

For the past month, she is idling a bit rough. Seems to miss. And there may be a miss at higher revs. Remember, she starts from cold in a flash. I recently replaced my fuel filter. Did the Seafoam and Howes (I always run Howes) to clean the injectors just in case.

Any ideas? Do I now need to replace my injectors?

Thanks,

Bruce in Tsawwassen

 

[prado t]

bruce, what type of fuel are you using , when it misses at higher revs do you see blue smoke? is there any fuel seepage on the IP or around the lines?
troubleshoot the fuel system first.if thats fine then you may want to a compression test. with that milage your 13bt is still brand new since it happens at idle all the way up cold or warm. i dont want to scare you or myself it may be a valve not seating properly i hope its not and just something simple
good luck
aaron

 

[A2B in a TLC]

I usually fuel up in Pt Roberts, Washington with Shell. I always add some Howes. No blue smoke at all. And it doesn't burn any oil. Not a drop. No fuel leaks either. The "miss" seems to be less when the motor is cold. And it does seem to come and go.

Thanks Aaron

B

 

[cody c]

i wonder if it could be sucking air in the fuel somewhere. a plugged line wouldnt be affected by heat so much as pressure(high rpm). Could be a problem @ the injection pump too.

 

[gooch]

hello bruce i think i have a similar problem to you and cant seem to find a solution if you come up with anything please let me know .....
thanks

 

[Whistler74]

I'll join in too - my 13B-T idles roughly, and it seems to be getting worse. No large amounts of smoke of any colour, starts fine, and fuel economy seems stable at about 26mpg (imp). The injectors have not been serviced, and at 160,000km I suspect it might be time.

I can't find any obvious leaks, but #2 injector seems to have a thin mist of either fuel or oil on it, and there is either oil or fuel on that side of the engine. I would think that a leaky injector line would spurt fairly obviously.

Any help is much appreciated.
Thanks

 

[bj74noob]

I have this problem too, but its generally rough when in gear. its more gentle when in neutral. I haven't checked the smoke though...

 

[lshobie]

Is it rough when you add a bit of RPM? or does it smooth out?

Try bleeding everything again, injectors, pump etc.

 

[bj74redrider]

This is a really old thread, but has anyone solved their problem? I have the exact same symptoms on my 13bt. New injectors, timing bang on, B5 as an additive, no fuel leaks I can find, no blue smoke, valves adjusted...I'm stumped.

 

[Tapage]

if you bleed it you got air in lines . ?

 

[bj74redrider]

No air at the injectors or fuel filter, all fuel lines seem ok and connections are tight and not leaking.

 

[jake2far]

Compression or leak down test?


Jim