low rpm driving/idle troubles
#1
Member
Thread Starter
Join Date: Jan 2012
Location: maquapit lake, NB, Canada
Posts: 117
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1999
Model: Cherokee
Engine: 1997 4.0 litre
low rpm driving/idle troubles
I'm having what i think is a fuel delivery problem. however, I'm not mechanically inclined. when i start up my jeep (always within the first 5 minutes of driving) after about 30 seconds of driving, i lightly apply the gas (say about 5%) and it feels like my tank is on empty (barely any throttle response). i will apply a little more gas with no effect. but when i put the pedal to about 30-40%, it works exactly as it should for the amount of gas i applied. also if it idles for a minute after i just started it up it will start to idle real rough and at a lower rpm. if i drive it to the store for a ten minute drive, i can leave it running while i go inside and come out to find it idling normally. i have recently changed my distributor cap and wires, and both o2 sensors. my check engine light is on but my superchip won't give me any diagnostic codes. i run only 91 octane gas and intend on sea foaming it soon. any suggestions will be appreciated. i apologize for writing half a novel
#2
CF Veteran
Join Date: Aug 2011
Location: Blue Springs, MO
Posts: 1,031
Likes: 0
Received 2 Likes
on
2 Posts
Year: 1993
Model: Grand Cherokee
Engine: 4.0L Laredo
I'm having what i think is a fuel delivery problem. however, I'm not mechanically inclined. when i start up my jeep (always within the first 5 minutes of driving) after about 30 seconds of driving, i lightly apply the gas (say about 5%) and it feels like my tank is on empty (barely any throttle response). i will apply a little more gas with no effect. but when i put the pedal to about 30-40%, it works exactly as it should for the amount of gas i applied. also if it idles for a minute after i just started it up it will start to idle real rough and at a lower rpm. if i drive it to the store for a ten minute drive, i can leave it running while i go inside and come out to find it idling normally. i have recently changed my distributor cap and wires, and both o2 sensors. my check engine light is on but my superchip won't give me any diagnostic codes. i run only 91 octane gas and intend on sea foaming it soon. any suggestions will be appreciated. i apologize for writing half a novel
*For the 'doesn't go when you pust the pedal' issue, I'd check the TPS.. It's right there by the IAC. It can be tested with a multimeter set to ohms (with key off) or volts with key on. It's like a volume control, a variable resistor. The ohmmeter (analog) should show smooth movement as you open/close the throttle. I think a quick search for TPS test will give you a more detailed testing proceedure. Hope this helps
#3
Member
Thread Starter
Join Date: Jan 2012
Location: maquapit lake, NB, Canada
Posts: 117
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1999
Model: Cherokee
Engine: 1997 4.0 litre
Idling issues are often due to the IAC valve being dirty. Remove it from the throttle body and clean the pintle and the seat it rests on. Don't twist or pull on the pintle, just clean the carbon off of it with carb cleaner.
*For the 'doesn't go when you pust the pedal' issue, I'd check the TPS.. It's right there by the IAC. It can be tested with a multimeter set to ohms (with key off) or volts with key on. It's like a volume control, a variable resistor. The ohmmeter (analog) should show smooth movement as you open/close the throttle. I think a quick search for TPS test will give you a more detailed testing proceedure. Hope this helps
*For the 'doesn't go when you pust the pedal' issue, I'd check the TPS.. It's right there by the IAC. It can be tested with a multimeter set to ohms (with key off) or volts with key on. It's like a volume control, a variable resistor. The ohmmeter (analog) should show smooth movement as you open/close the throttle. I think a quick search for TPS test will give you a more detailed testing proceedure. Hope this helps
#5
Member
Thread Starter
Join Date: Jan 2012
Location: maquapit lake, NB, Canada
Posts: 117
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1999
Model: Cherokee
Engine: 1997 4.0 litre
Thread
Thread Starter
Forum
Replies
Last Post
ROCKRIDGE 4WD
Vendor Showcase
13
11-05-2019 10:58 AM
idahomike
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
84
06-17-2016 07:39 AM
xjnoah
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
0
09-16-2015 02:29 PM
Girlski
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
11
09-15-2015 03:31 PM
Jicki Rough
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
1
09-02-2015 09:36 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)