84 2.8 Power loss when warm

When my 84 warms up (after 15 min or so of driving) something happens that causes idle to drop & it barely has enough power to get off the road. I have fixed the vaccum leaks, changed the carb, fuel pump, plugs & pcv.

Any ideas would help.

Thanks,
Chris

try changing the O2 sensor. that might do it.

I thought that O2 sensors were only used on fuel injected engines, this one has a carb.

Chris

CRMW said:

I thought that O2 sensors were only used on fuel injected engines, this one has a carb.

Chris

Click to expand...

I have a 84 2.8.. no 02 sensor.

your title is confusing me..

is this a idle problem, it won't idle when warm. or is this a feels sluggish through all engine modes, accelleration and crusing.

it maybe your idle is set to low after the engine gets to warm enough and the choke disengages..

The lower idle is not the problem, but a symptom.
When the engine warms up, it is like the power is switched off. The idle lowers, & the engine bogs down, sluggish is a major understatement. The engine takes longer to rev up, and backfires even in neutral.

It happens all at once, as if the high idle kicks off & the air is mostly shut off to the carb.

Its kind of hard to describe!

Chris

now I don't want you to get pissed at the next question..

but did this happen before or after the carb change? :flame:

it almost sounds like one of your little thermal vacum switchs is providing vacum to the wrong port ...

thats why I asked if it happend before or after.. maybe you routed a vacum line wrong.

if you can keep it running long enough after it warms up.. pop the aircleaner off.. and push on the rod that goes straight down into the carb.. its on the right hand corner(if I remember) of the carb.. see if it smooths out.

does it smell rich? or maybe its starving for fuel...

This has been happening since I got the Jeep, and I can't gaurentee the vacuum lines were routed correctly when I got it, the P.O tried to fix the problem. It will idle when warm, so I'll try pushing down on the rod when I get home.

I thought it might be starving for fuel, & that is why I changed the fuel pump.

Thanks for the lead.

Chris

do you have a manual or automatic? california emmisions or not?

I will post a pic of the vacum diagrams when I get this info.

Thanks RINGKONG

It an Auto without Ca emmissions.

Chris