I have a 93 pickup 22re 4x4 5 speed. Starting this morning when i turned the truck on i noticed the engine sounds a little off. Kinda like one cylinder isn't firing. When im driving it is very sluggish until its in very high rpms. any help would be cool thanks.

 

Some history would help, what services have been done (or not).

 

I can't really say, just got the truck a few weeks ago. It has about 180k on it.

 

First I would down load the FSM
http://www.ncttora.com/fsm/

Then I would start by checking for vacuum leaks, and check spark plugs, maybe a tune-up you got to start somewhere.

 

Ok thanks a lot. I just changed out the spark plugs and wires but it's still bogging and sputtering. What are some key places to check for vacuum leaks? Thanks, Mike

 

Mike, there are no key places. Check all the vacuum lines. What brand spark plugs and wires did you use?. Are the plugs properly gaped?

 

Plugs are NGK and properly gaped. Wires are Napa brand. After going through the FSM i think its either the o2 sensor or the MAF. I went out this morning and checked all my vacuum lines, i didnt see anything out of the ordinary. When i started her up she ran perfect for a few minutes then started bogging down again once i started driving. Any ideas on which part i should go with first? o2 or maf? thanks

 

Tested the o2 sensor and it read 9.5 ohms when the fsm says 5.1-6.3 ohms. Could that be my issue?

 

Just went to Napa and put in an oem re manufactured MAS. The truck sputtered and stalled, plus the check engine light came on. So i put the old one back in and its drivable but still very sluggish at low rpms.

 

This is just a guess but possible cold temp sensor is bad causing it to dump more fuel thus causing bogg, but not sure maybe someone else here can assist also. Bad o2 can also cause real bad gas mileage. Don't want to see you throw a bunch of parts at it if not needed.

 

Yeah I appreciate it. I think I'll check out the cold temp sensor next. I remember now that the thermostat was acting funny the day it happened.

 

I looked through the FSM and didnt see anything about a cold temp sensor. Is it just the regular thermostat or something else?

 

Look under MFI section just above cooling section cold start injector and cold injector time switch.

 

The problem has gotten considerably worse today, truck wont even run for more than 2 seconds now. Taking it to the shop next week, ill post what the issue is once they find it. Thanks for the help though ksti.

 

Sorry, I wasn't much help it looks like, but yea let me know what they find.