Bogging down under load! Please help!

[kingmatt16]

I have a 89 Wag with 95,000 on it. It starts flick of the key in the morning and runs great under no load. If you poke the throttle lightly or under 1/8 throttle it takes off great. More than that it bogs a bit, which is especially noticable when it shifts from 1st to 2nd. If you Hit it more than 1/2 throttle it pops. Gets worse with more people in the car or more load. I just rebuilt the carb to see if that would help, no difference. In fact, inside the carb looked great. I have adjusted the timing, checked vacuum lines, new plugs wires, fuel pump, filters, tfi upgrade. Another thing that may be related...she is hard to start sometimes when engine is warm...in other words sitting for 30 minutes or more, starts great when hot (few minutes after shutoff) or cold. The problem is definitely load related. The more load on the engine, via throttle pressure or just plain weight in the car.
Any suggestions please?
Thank you,
Matt

[64Trvlr]

Did you check the coil to make sure it's putting out 100%?
:cool:

[kingmatt16]

Thanks for the reply. How do I check the voltage at the coil? Also, when I did the tfi upgrade, I did not use a resistor. Should I use one, and if so, what is the size of the resistor I need, and which wire do i hook it up to?

Thank you,
Matt

[Bombadier]

my chero does something similar from time to time, usually when cold.....for the first minute or so, if i give it more than gradual throttle, the engine bogs, and if i mat the gas, i'm liable to hear a cough/pop through the carb.....
but otherwise, it starts like a champ cold, and runs great otherwise, but the Jeep does NOT like stop-go-stop driving (as in rush hour)....too much of that and it will stall period and not start until it's cooled off a bit. my temp gauge works fine, but in such conditions, my oil pressure drops WAY low.
....
anyways, yeah, check your coil....other than that, i'm still trying to figure these kinda things too. :rolleyes:

[SpruceMoose]

almost sounds like 2 problems. running lean, which will cause increasingly worse problems as the load is increased. and will include backfiring thru carb. also, sounds like a vapor lock problem after shutdown, caused by the engine compartment getting heat soaked. get the fuel lines away from the top of the engine bay, and/or try an electric pump mounted on the frame rail back by the tank.

sm.

[DerJeep]

Don't forget the catalytic converter. It can clog up and cause your engine to bog down under load.

[kingmatt16]

Catalytic converter is new along with who exhaust. THe egr vlave is disconnected and has a nail in the tube that runs to it. Could it be a bad egr? WHat about a cto switch? Vacuum advance?

Thanks!

[DerJeep]

I doubt it is your EGR valve. If it were stuck open you would experience a very poor idle and possible stalling. This does not seem to be the case.

Carbs can wear out to the point that a rebuild will not buy you anything. I am probably at his point myself. When I adjust my right mixture screw it has absolutely no impact on the engine. I can turn it in all the way or out and RPMs do not change. I rebuilt the carb making sure to blow out all the passages, set everything correctly but that dang mixture screw still does nothing.

[JINGA]

Sounds like something I had:
A thread on something similar (http://www.ifsja.org/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic;f=2;t=005700)

I finally took to a "local" shop. They said they "induced a backfire" and it cleared up. Jeep drove fine for awhile, but then clonked and died again.
The saga continues. (http://www.ifsja.org/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic;f=2;t=008148)

The mechanic asked me what kind of gas I used. All thinga are pointing towards a fuel problem with my Jeep. Maybe yours too?

I'm finally going to have some time in the next few weeks to get some work done on my ride. Good luck on yours.