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low rpm driving/idle troubles

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Old 03-19-2012, 10:42 PM
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Default 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
Old 03-20-2012, 04:03 PM
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kjc
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Originally Posted by toddhalbot
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
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
Old 03-20-2012, 10:58 PM
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Originally Posted by kjc
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
I'm sure it will help once i do some research. you used a lot of words that are new to me haha I'm not very good at this sort of thing
Old 03-20-2012, 11:49 PM
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You are wasting money using 91 octane. Just use 87. Has nothing to do with your problems though.
Old 03-21-2012, 02:30 AM
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Originally Posted by 944.0
You are wasting money using 91 octane. Just use 87. Has nothing to do with your problems though.
it can't run on anything but 91 with the chip i have in it. it gives me an extra 40-50km a tank (the chip)
Old 03-21-2012, 03:08 PM
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Originally Posted by toddhalbot
it can't run on anything but 91 with the chip i have in it. it gives me an extra 40-50km a tank (the chip)
How does it do that? Lean it out? Maybe it's running too lean?
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