Forum Index
Jeep Horizons HomeLinksJeep Horizons Tech Write-upsJeep newsLand useContact

 Watched TopicsWatched Topics   FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

no power when hot

Goto page 1, 2  Next
 
Post new topic   Reply to topic     Forum Index -> Cherokee Forum
View previous topic :: View next topic  
Author Message
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Sun Jul 29, 2007 1:43 pm    Post subject: no power when hot Reply with quote

hi guys, I hope you can help
I just swapped out a 4.0 and tranny from one jeep to another to the same model year, 89. It starts with a lot of cranking before it gets gas, was like that before, the problem is after it gets hot it hesitates and backfires with no power. When it gets hot the whole front end seems to radiate heat and a lot of it ,but it doesn't boil over. when its cold it seems to run like a dream. I've changed the cps and checked the thermostat (180) and I'm switching that to the 192. One of the factory temp sending units isn't attached (One on the radiater) because the auto tranny cooler plugs into that. I'm running an analog after market gauge so I can see the temp as we speak, took a break to get ideas before I go back into the heat. any ideas would be great. It ran fine until we swapped them across.
Back to top
View user's profile Send private message
jppilot61
Moderator
Moderator


Joined: 06 Mar 2004
Location: Tappahannock, VA

PostPosted: Sun Jul 29, 2007 2:44 pm    Post subject: Reply with quote

Is your electric fan running? -- Should run when it gets real hot, or when you have A/C (or Defroster) on.

Is that sensor (on radiator) the one to senses temp for Electric fan?

Just a guess. . .
_________________



1992 XJ Laredo
RE6130 4.5" XJ Super-Flex Kit
RE1801 Slip Yoke Eliminator Kit NP231
Back to top
View user's profile Send private message
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Sun Jul 29, 2007 3:04 pm    Post subject: Reply with quote

the fan works, I just recharged the A/C and all of that stuff works. The dash gauge isn't hooked up and I was wondering if that is connected to the computer. I also just replaced the O2 sensor and I am on my way to get a T to reconnect that gauge.
Off topic, but when I put the engine under a lot of load, heavy acceleration, the fan inside the cab shut off, is this normal?
Back to top
View user's profile Send private message
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Sun Jul 29, 2007 4:01 pm    Post subject: Reply with quote

no T found, its 5/8 so Lowes doesn't carry it. I'll start it and see what it does without it. I remember that it wasn't hooked up on the doner jeep either so I won't stress on it
Back to top
View user's profile Send private message
Brad The Best
Member


Joined: 14 Jan 2007
Location: Kamloops B.C Canada

PostPosted: Sun Jul 29, 2007 8:12 pm    Post subject: Reply with quote

that sensor is actually for your computer Smile

the thermostat only controls minimum temperature .

unless you have a sensor right in front of the valve cover , i can't remember were they put it on 89 .
Back to top
View user's profile Send private message Send e-mail MSN Messenger
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Sun Jul 29, 2007 8:16 pm    Post subject: Reply with quote

I have an after market temp gauge now. temp gets to 200 now but as soon as it gets above 180 is when this problem starts, could it be the throttle position sensor or a sticky choke? when I disconnect the tps, nothing changes. still backfires like a timing problem but the timing advances when I accelerate. under load it chokes out when hot.
Back to top
View user's profile Send private message
Brad The Best
Member


Joined: 14 Jan 2007
Location: Kamloops B.C Canada

PostPosted: Mon Jul 30, 2007 6:42 pm    Post subject: Reply with quote

there is no choke plate its efi , all it does is richen the mixture when the sensor senses that its cold .
Back to top
View user's profile Send private message Send e-mail MSN Messenger
Brad The Best
Member


Joined: 14 Jan 2007
Location: Kamloops B.C Canada

PostPosted: Mon Jul 30, 2007 6:43 pm    Post subject: Reply with quote

no chance on any fault codes eh ?
Back to top
View user's profile Send private message Send e-mail MSN Messenger
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Mon Jul 30, 2007 8:03 pm    Post subject: Reply with quote

my book doesn't explain how to read them, can you tell me the set up and give me an idea what the best manual is to buy. I have the chiltons and it sucks. My friend has a haynes and it is much better than mine for diagrams. 89 cherokee, 4wd, 4.0 liter, auto. The haynes says what to do with an 91 or newer but mine doesn't have a check engine light, it does have an emmision light but that is on a timer with the speedo and the O2 sensor.

I did find out today that the fuel pressure is at 20 and won't change no matter what( crimp return line, disconnect regulator, so I tried to replace the fuel pump but the Auto Zone model won't fit through the hole. I guess I need factory replacement$$$$$$. Just Empty Every Pocket.

The EGR has been replaced, it was bad. fuel filter replaced, just in case. Reason is the Jeep sat for 4 years and I believe the fuel has gummed up most of the fuel system. The motor and all fuel system except for the lines back to the tank are out of a doner that was running up until the swap including the computers and some of the wiring. CPS and O2 sensor replaced, meter wouldn't read on the cps until I got the jeep home and waited for it to cool so it could be removed. I hate replacing stuff this way but its stuff that I don't want to replace in the snow in -5 degree weather either.

after the fuel pump its the regulator if the pump doesn't fix the bigger problems. Another symptom is the vent vaccum seems to shut off when I accelerate, is it due to the engine working so hard with the fuel problem? It seems to be getting worse, the power problem. Any ideas would help.
Back to top
View user's profile Send private message
jppilot61
Moderator
Moderator


Joined: 06 Mar 2004
Location: Tappahannock, VA

PostPosted: Tue Jul 31, 2007 1:46 am    Post subject: Reply with quote

utahhandyman wrote:
Another symptom is the vent vaccum seems to shut off when I accelerate, is it due to the engine working so hard with the fuel problem? It seems to be getting worse, the power problem. Any ideas would help.



Vacuum Leak?
Back to top
View user's profile Send private message
Brad The Best
Member


Joined: 14 Jan 2007
Location: Kamloops B.C Canada

PostPosted: Tue Jul 31, 2007 5:58 am    Post subject: Reply with quote

jppilot61 wrote:

Vacuum Leak?


agreed , for the vents not opening and maybe the jeep not running well.

you let your jeeps it for a few years with out stablizer in it then fired it up and drove it ?

there is your problem , change the filter anddrain the tank fill it with fresh gas , run some injector cleaner through it .

sounds like your all ready buying a fuel pump next will be the regulator . i believe it should be around 35-40 psi for the old non-ho engine .

chilton is made by haynes , for some reason the haynes seem to be better .

maybe it just has the emissions timer , i could be wrong . have been a 1000 times before .

the only other thing is the tps , i don't know why it would only do it hot but hey who knows .

hows charging voltage ? low voltage can make everything go wonky .
Back to top
View user's profile Send private message Send e-mail MSN Messenger
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Tue Jul 31, 2007 6:18 am    Post subject: Reply with quote

voltage is fine. I bought the jeep for $500 from the owner who left it in the garage with blown engine and bad tranny. bought a second doner jeep for $500 with a recently rebuilt engine and good tranny. It ran well before the transplant. After the pump gets switched today we'll see how franken jeep runs and then go on to the possible vaccum leak. I couldn't find one before but this power problem has been getting worse. Now it has no power as soon as it starts. so I believe the pump is a major problem, we'll see what other problems change after its replaced. And I have run Half a tank of fresh gas through it so hopefully any bad gas is gone now, it had less than an 1/8 of a tank in it before I filled it. Thanks the suggestions, I'll let you now tonight wat has changed.
Back to top
View user's profile Send private message
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Tue Jul 31, 2007 6:21 am    Post subject: Reply with quote

I did test the tps yesterday and it said it was good although the manual didn't really have a test for the tps with 2 different connecters. But the resistance changes were nice and smooth. After the pump is changed we'll see whats going on then. thanks
Back to top
View user's profile Send private message
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Tue Jul 31, 2007 6:24 am    Post subject: Reply with quote

And for anyone who wants the left over shell Jeep it has a 4 inch lift, sway bar disconnects and 32 inch tires. $700 to tow it away. The body is shot and the axle ratios don't match front to rear.
Back to top
View user's profile Send private message
utahhandyman
Member


Joined: 29 Jul 2007
Location: salt lake city

PostPosted: Tue Jul 31, 2007 8:11 pm    Post subject: Reply with quote

replaced the pump at $230 dealer dollars for the pump only, had to reuse fuel level sender and housing. started right up and ran great. but the fuel gauge doesn't work. try again tomorrow
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic     Forum Index -> Cherokee Forum All times are GMT - 8 Hours
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Visit links4jeeps.com for write-ups, forums and clubs




Jeep®, Wrangler, Cherokee, Liberty and Grand Cherokee are copyrighted and trademarked to Chrysler LLC.
jeephorizons.com is not in any way associated with or endorsed by the Chrysler LLC.
All other content is copyright Jeep Horizons 2004-2008.
Tech write-ups Links Discussion board Land use News Site Map Terms of Use

Powered by phpBB © 2001, 2005 phpBB Group