I have searched the forum and have not been able to locate a similar problem so I'm looking for help. I have a 93 4runner with 230k on it. Cranks fine and will run great for about 30 minutes but then starts hesitating and stumbling as I go up a slight incline. Very consistant in that I have a 45 minute ride to and from work each day and it always happens in the afternoon once it gets above 80 degrees outside. I can pull over to the side of the road and cut the car off and start it right back up and she runs good again for the remainder of the trip. Any ideas?

 

First thing I would start with is the ignition system. Obviously your truck is misfiring for whatever reason.

What is the condition of your:

Plugs
Wires
Distributor cap
Distriburor rotor

From there we can look at more in-depth advanced stuff.

 

EGR

about the time it takes the computer to go open loop and "Start messing with stuff" ie EGR called... could be a vacume leak on the EGR... but either way id say check out the EGR system....

 

New plugs, wires, cap and rotor. Also checked the timing and she is right on the money per the Toyota info tag at 10 degrees.

 

Checked EGR and for vac leaks. EGR tested okay but I did find a crack in the air intake hose right at the intake to the injector body. I pulled the hose an taped it up to see if that would help. Test ran and it looked okay, however I got a CEL and checked the codes last night to find a 26 flash code. Truck seems to be running good right now. Also adjusted timimg from 10 degrees btdc to about 14 degrees after reading some other postings on the forum about increased gas mileage and performance as well as run some seafoam cleaner through the system. Power definitely increased but that may be causing the code to be set. Any ideas about how to get around the code?

 

Dumb question but what is the EGR?