Need help 1998 4.0

Post by **shmoken875** » Thu Sep 03, 2009 10:53 am

TerryD wrote:Your fuel pressure looks OK Randy. Do you have a multi-meter? If so, the Chilton's book should tell you how to ohm out your TPS to check it and may even have a procedure to check the MAP sensor.

I'm sure somebody around here has a multimeter I don't though. This is where I may need a hand though as I'm absolutely lost when it comes to electronics.

YouTube · Post by **TerryD** » Thu Sep 03, 2009 11:15 am

The book should tell you what to do in a step by step manner. Just follow the directions.

What you should have is just your basic potentiometer. Three pins/wires. Two of them will have a constant resistance between them. The third will change as you move the lever on the side. As this changes, look for dead spots where the resistance drops/spikes/doesn't change. This will indicate a bad TPS.

The MAP sensor, I'm not sure about. You'll probably have to have a vacuum pumper (which I do not have) and a 12V or 24V source to put across the terminals. I'll try to search online and see what I can find.

YouTube · Post by **TerryD** » Thu Sep 03, 2009 12:06 pm

Testing the MAP sensor:

http://www.cherokeetalk.com/forum/f22/m ... dure-1261/

One guy in there has a 98, the other a 99. That should be the right procedure. I've got a 97 Service Manual at home, I'll try to check it out next week when I get there to verify.

Post by **BadnewsCJ** » Thu Sep 03, 2009 12:32 pm

hippie has a multimeter he says you can use rantotaur

Post by **shmoken875** » Thu Sep 03, 2009 3:15 pm

Thanks for the info terry. Hippster I'll probably take you up on that multimeter early next week. But from now till Sunday night all that's on my mind is football, ATL, titties, and beer, so this project is officially bumped to next week.

Post by **BadnewsCJ** » Fri Sep 04, 2009 12:33 pm

shmoken875 wrote:Thanks for the info terry. Hippster I'll probably take you up on that multimeter early next week. But from now till Sunday night all that's on my mind is football, ATL, titties, and beer, so this project is officially bumped to next week.

ma man!

Post by **shmoken875** » Mon Sep 21, 2009 6:58 pm

update:
Put James TPS on......still ran like crap
Put James TPS and MAP on.....still ran like crap
CEL came back on

rough idle doesn't really start until its warmed up

gotta go buy a code reader, Advance won't let me borrow it and I can't get the jeep there.

also going to try and test the wiring with hippies multimeter, still trying free stuff first.

YouTube · Post by **TerryD** » Mon Sep 21, 2009 7:29 pm

When's the last time you put plugs/wire/cap/rotor on it?

Post by **shmoken875** » Mon Sep 21, 2009 11:07 pm

TerryD wrote:When's the last time you put plugs/wire/cap/rotor on it?

probably too long...cap and rotor never; plugs and wires like 25k ago
I'll pull the cap and plugs and check them

Lukipela · Post by **Lukipela** » Tue Sep 22, 2009 12:13 pm

shmoken875 wrote:When I was replacing the upstream O2 sensor I rounded it off and being frustrated and having class in an hour, took it to Auto Repair to have them remove it. He called and said the threads twisted off in the bung so I told him to weld a new one in. Instead of a new bung they welded a nut over top of the messed up bung, which pulled the O2 sensor back (out of the down pipe) by about 1/2", would this effect its operation?

Having it that far out of the tube might effect it slightly but i dont think it would be enough to be your problem, though you should probably get around to fixing that. Definitely check the plugs and wires and all, just because the computer is giving you some code doesnt mean that thats the actual problem.

Post by **alk1174** » Tue Sep 22, 2009 1:26 pm

A few years ago the civic started giving us problems hesitation sluggishness and the CEL would blink on and off. Changed the bosch platinum plugs over to OEM plugs and everything was fine after that. I also had a carbd 87 yota that started missing and hesitating under acceleration. Changed the plugs wires rotor and cap and everything was fine. This might not help you but sometimes its just the simple things.

Post by **Brett** » Tue Sep 22, 2009 3:23 pm

auto zone does free diagnostics. This might help. 2 cents worth.

Brett

Post by **shmoken875** » Tue Sep 22, 2009 6:06 pm

Brett wrote:auto zone does free diagnostics. This might help. 2 cents worth.

Brett

don't think i can get there without becoming a hazard

Post by **Timmah** » Wed Sep 23, 2009 12:01 am

shmoken875 wrote:
Brett wrote:auto zone does free diagnostics. This might help. 2 cents worth.

Brett
don't think i can get there without becoming a hazard

It's downhill after you get to main street!

Post by **ford150** » Wed Sep 23, 2009 10:34 pm

have code reader if someone needs quick check