Head scratching here

[vankc]

Well hadn’t driven my 85’ in a few weeks so went to start up and got her running like I normally do with the choke on and she finally cranked up and got going. Sounded normal as always then I noticed it sounded like it started running on 5 cylinders (misfiring) then proceeded to get worse like multiple cylinders misfiring then died. So im thinking maybe the coil has gone bad or plugs. Any thoughts?? I need to do some analysis to see if say the plugs are getting spark to them etc. but had to run to an apt.

 

[John Smith]

I'd start with testing the coil and igniter, my money is on one of those being the issue. Then pull the distributor cap and have a look there also. Highly doubt you would have plugs failing one after another.

 

[vankc]

yeah that was what I was thinking as well. It cranked up and was on Choke and was running just fine then I backed off the choke a bit to idle it down and was going to let it warm up and then that is when I noticed it like misfiring or seemed like it was running on less and less cylinders so my gut tells me my coil or ignitor shot craps on me. I saw a thread on here on how to use a 9v batter to test the coil so I will start the process of elimination

 

[vankc]

Thanks for your reply @John Smith

 

[OSS]

From my understanding based on Marv Specter’s advice, (not personal experience) if the igniter goes bad, the engine won’t run. We didn’t talk about symptoms leading up to an igniter failure, but what I gathered, suddenly the engine will no longer run.

The igniter detects the very faint signal from the hall-effect sensor in the distributor and then boosts it up higher so that the coil can use it.

 

[vankc]

Can one still find an igniter??

 

[vankc]

Answerd my own question on the Igniter >>> Long gone. Used is the only option - sorry about that question.

 

[vankc]

Well I thought I was out of the wood shed unitl >>>>>> before >>>Well I started thinking here and check the fuel bowl glass and noticed zero fuel in it so this had happend before so I put a little carborator cleaner in the Venturi brass bowl vents and let it set and she fired up and a bit rough. So I took her out for a spin and she ran ok except when first starting out she was a bit jumpy or like running cold, but then again she hadn't ran in a bit. SO i ran ran for a bit longer and the performance got back to normal. Then went to turn the engine off and experience a little "run-on". Came back after a bit and she started right back up and I ran her for a while and seemed to running really good, went and put some Sea Foam in the gas and ran her some more and she was purring. Stop by filled up the tank with new gas and she started right on the dime "Also no "run on after turning the engine off". Went down the road and came to a stop light and she just died. Fortanute that a guy at the gas station that just paid me complement on the truck was next to me at the light and volunteered to help me get the truck out of the intersection and into a vacant lot. I set there for a few and tried to start her up again and she fired up but rough and misfiring. Limpped home barely by keeping the RPM's up a bit and got her in the garage. WOOZER... So now scratching my head of why in the heck everything is running so smoothly and then all hell break out. Thoughts?

 

[John Smith]

With your latest description it sounds like you may have a failing fuel cut solenoid. When you turn the ignition key to the on position you should hear an audible click at the carb. This is your fuel cut solenoid opening. If this is failing it explains why your truck ran fine warming up but started to die when you pushed in the Choke. With a failed fuel cut solenoid the truck will run with the choke, but not without. It also explains why you had no fuel in the carb window. Also explains why you got the run on when you turned off the truck. The solenoid makes sure you have no run on after turning off ignition. So all things now point to a failing fuel cut solenoid. Look there.

 

[vankc]

would a faulty Fuel cut solenoid have the potential to cause misfires @ low idle as well?

 

[OSS]

Check the fuel filter. Or replace it.

 

[Shredder]

My brother has a 85 and recently had a similar problem. Turns out it was a dirty fuel tank. The fix was to drain the tank and flush it out, and get new fuel pump and filter.

 

[Spike Strip]

Fuel filter is cheap and very easy. Try that first. The OE Toyota is best, but you can try it with an VatoZone special

 

[yotadude520]

My 60 was having fuel delivery issues and it turned out to be a bad vacuum line on the vacuum fuel cut off switch.

 

[CruiserTrash]

The choke knob can cover up a lot of potential problems - usually fuel or vacuum related. Have you check for vac leaks or just replaced all the crusty old vac hoses? Carb rebuilt ever?

 

[65swb45]

Sticking needle. Going between flooding and starvation. Time to open up the carb. If you find shellac in the bowl, then the needle is the victim, not the culprit, and you’re going to end up doing it again until the shellac is gone. Fuel filter won’t stop anything in the lines that is past the filter.

 

[vankc]

Thanks all went to do a bit more investigation and started it up (choke out), did its normal thing with the Choke all the way out and idle'd (high rev) and then after a bit it started to idle down even with the choke fully out but a faster idle than say its normal running idle, but again a bit rough overall. As it was warming up I noticed some fumes (not normal in the past) so started looking with the flash light and I believe I found the culprit. See pics, this dosen't look right and was never an issue in the past. Looks like I have some fuel leaking from the carb. Not sure if this would cause my issues with poor running but something that I need to address. Maybe time for a carb rebuild. Attached are some pics.

 

[Spike Strip]

That's your slow-cut valve. The leaking is not your issue, but it is an issue that needs addressed. That Slow cut valve is an emissions component.

Time for a rebuild. That SCV is long no longer available, but a competent rebuild will plug the leak.

65swb45 above is a LC carb guru (Mark's Off Road in Burbank, CA) Call him and ask about the rebuild and turn-around time 818-953-9230
Website addy is in his sig line.

Also, if you're de-smog'd, you can buy an aftermarket clone or even a new, world-spec carb (no smog or HAC provisions) from Toyota.