ttrmike

I have been trying to complete my toyota pickup restoration and am running into some problems getting the truck to run right. The pickup is a 1987 Toyota 4X4 standard cab short bed with a federal 22R.

The truck runs on high idle OK, it starts off a little rough but then picks up to the proper speed. It runs for maybe 3min and then drops off of the high idle. This is where all the problems begin, it drops off of high idle and and starts to idle real low, is shaky and misses. The way the DUI distributor is hooked up is direct vacuum and advances at idle. A couple of days ago the truck idled GREAT, but now all of the sudden it wont. The seems to be that the distributor isn't advancing, like there isn't any vacuum at idle. I have tried every thing I know and nothing has worked. If you have any ideas I would greatly appreciate it.

The truck has:

-NEW motor
-remanufactured carb
-DUI ignition system
-Denso platinum +4 sparkplugs
-good plug wires
-new EGR valve
-new EGR valve modulator
-New vacuum switch
-New VSV
-the Air injection system is working
-new PCV valve
-new fuel filter
-new air filter
-all new vacuum lines
-I have triple checked all vacuum line routing
-fuel cut solenoid is working
-no noticeable vacuum leaks
-idle screw can be adjusted to no avail
-idle mixture screw can be adjusted without any results
-timing is correct
-no blow fuses
-no loose connections at ECM
-the AAP valve is fine
-both BVSV valves function
-8 gallons of new gas was put in the truck along with sea foam
-float level is fine
-no apparent exhaust leaks
-new exhaust system including new 2.25in cat

Lumpy

Almost sounds like a vac leak...

ttrmike

Well, today the truck didn't want to idle in the morning but after about an hour it started to idle again on its own, and the distributor started advancing again. Then I took the truck for its first drive, about 10 miles of pretty flat pavement. When I got back the truck wouldnt idle again. So, I shut the truck off and let it sit for about 45min and started it back up to move it, and it started idling again. The truck seams to clear it self as the problem goes and goes. Could it be something clogging the fuel lines even though I have a new fuel filter? Would cleaning the charcoal canisters have any effect?

This thing is making me pull my hair out!

sarmoby

Mike- I'm a newbie on the board so take this with a grain of salt....

See my post todayhttps://www.yotatech.com/forums/f116/87-22r-carb-sr5-cluster-swap-tach-issues-186464/- your problem sounds eerily familiar.

Will it run cold?
Do you have a tach add on or added the new ignition in place of the ignitor?
That may have sent some weird signal to the emission controls that help run the truck. Mine only acted up once up to temp.

Hope this helps some
Scott