jjyoda_86

I have a 93 that every time I start it stone cold it hesitates on acceleration and smells like its running very rich. I have new plugs and wires, timing OK.
I scoped the coil but after I had drove it to the shop and it scoped out fine. It only hesitates when its cold for the the first few minutes when its warming up after warm up it accelerates OK. still stumped and seems to me that these v6 3.0 should get better then 13mpg around town. any Ideas im open for and will try it out if it sounds like it will help. another stumper is that after cruising around the hills buck hunting hit a main road and stomp on it to get going down the road and the truck is bogging itself out and im full throttle, put it in neutral and revs up fine, I put back in gear and it does the same thing. after shutting off and restarting it drove fine. Its done it to me 3 times now, but still have no ideas of why its doing that.

jrod1407

i'm having the same problem when cold it seems to hesitate only when cold. what is your timing at? have you had any luck lately?

Swim

Hmm, Ok for the cold problem. Have you checked your cold start injector and cold start injector timing switch?
My engine will do the same stumble until it's warm (Approx 172f) but that's just a fact of life. Let the car warm up, then stomp on the gas.

I run a very modded 3.0, 33's, 4.88's, and I get 15mpg in town, 19mpg highway. I also don't obey speed limit signs, uphill, downhill, or flat out.
Timing is key with these engines, and I have spent HOURS timing this thing. Get out your timing gun and start figuring out where your engine runs best. I have an excel spreadsheet for my engine ranging from Stock to 20^ BTDC. If you take the time to learn how your engine will perform at the different timing intervals, you can set it so you have the perfect blend of power and mpgs.
As for the bogging down, my old engine did that. Still to this day have no idea why.

jrod1407

any luck yet? my idle now sits at a thousand and i have no idea what's wrong

jjyoda_86

so what am I checking for on the cold start timing switch? also on my cold start injector it had solid pressure when I pulled it off when engine was cold still trying to figure out how to plug off the port to intake mani so i can start the truck and see if its still pumping fuel after the truck is running. also I recently pulled codes to see if any and had code 14. i just put new plugs and wires on a while back also ohmed out coil and was square wave like its supposed to. I also just recently replaced the fuel pulsation damper since screw was missing. but still this thing seems like it is drinking way too much fuel

TNRabbit

The worst offenders for fuel mileage are big tires, vacuum leaks, & auto tranny~

mschein1

Subscribed, I have the same issues.

TNRabbit

You can check for vacuum leaks with a propane/MAPP gas torch (UNLIT!!!) with the engine idling. Run it all around the intake & vacuum hoses & listen for an idle up. There will be your culprit(s).

Fishaa

I had this a while back. Seems to be much better now. Still happens a little bit but nothing like before. The only thing that has really been fiddled with was timing. Its at 10 degree's advanced now I believe. Idles much lower when warm (like 500rpm if im lucky) but has a little more pep to its step.

Might also look at changing the thermostat next service.

Swim

10^ advanced. Is that advanced from stock, advanced from zero, advanced from the last point it was set at...?

10^ BTDC is usually stock.

markwils

I'd like to re-open the discussion if anyone has new info. I have the exact same problems. I find it happens if It is cold and I either stall it or lug it to very low idle. Then it is like the mixture goes all funny and it runs awful, hesitates and sometimes stalls.
Has anyone resolved this??