Troubleshooting sudden gas mileage drop off
11-08-2005, 08:33 AM
#1
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Troubleshooting sudden gas mileage drop off
Okay...
I am looking for ideas here....
About a month ago, I rode from Dallas to Houston, and I made what I thought was good mileage, about 26 MPG
Now this weekend, I've have noticed a significant drop off...and I am trying to find a solution here's what I know:
1. I have an exhaust leak, probably in the front manifold. I am replacing the gaskets and studs this weekend.
2. My O2 Sensor has a small dent in it, I may replace it, but as expensive as it is, I like to know if it can be checked before I just toss it and get a new one.
3. I replaced my spark plugs about this time last year, and I may consider doing that again when I inspect them this weekend (I use OEM NGK's from the dealer).
4. I am planning to run SeaFoam through my intake (I do this every 6 months or so).
5. I am going to clean and/or replace my K&N filter.
6. My VTC harness (which I keep grounded) recently showed signs of an oil leak. I had to replace the harness, individual wires that I soldered together to again kill the clacking. BEfore I did this, I noticed a power loss , as well as the gas milage loss, but the power has seemed to return.
Any other things I should replace/clean/inspect?
Knock sensor and MAFS were replaced about 2 years ago
I am looking for ideas here....
About a month ago, I rode from Dallas to Houston, and I made what I thought was good mileage, about 26 MPG
Now this weekend, I've have noticed a significant drop off...and I am trying to find a solution here's what I know:
1. I have an exhaust leak, probably in the front manifold. I am replacing the gaskets and studs this weekend.
2. My O2 Sensor has a small dent in it, I may replace it, but as expensive as it is, I like to know if it can be checked before I just toss it and get a new one.
3. I replaced my spark plugs about this time last year, and I may consider doing that again when I inspect them this weekend (I use OEM NGK's from the dealer).
4. I am planning to run SeaFoam through my intake (I do this every 6 months or so).
5. I am going to clean and/or replace my K&N filter.
6. My VTC harness (which I keep grounded) recently showed signs of an oil leak. I had to replace the harness, individual wires that I soldered together to again kill the clacking. BEfore I did this, I noticed a power loss , as well as the gas milage loss, but the power has seemed to return.
Any other things I should replace/clean/inspect?
Knock sensor and MAFS were replaced about 2 years ago
11-08-2005, 09:46 AM
#2
Senior Member
Join Date: Dec 2004
Location: EU Scandinavia
Posts: 4,323
- ECU tests contain one tst specific only for O2, read also FSM
see http://www.cardomain.com/ride/748507/21
- EGRC temp sensor
- Hand brake; wire stuck
- gas leak
- intermittent injector leak
see http://www.cardomain.com/ride/748507/21
- EGRC temp sensor
- Hand brake; wire stuck
- gas leak
- intermittent injector leak
11-08-2005, 10:06 AM
#3
Senior Member
Join Date: Mar 2002
Location: Ontario, Canada
Posts: 1,114
You may want to visually inspect your vacuum hoses to see if any have cracked ends. Those cracks develop 'all of a sudden' and cause all kinds of nasty effects. Is your braking feels worse by any chance? That would point at vacuum as well.
11-08-2005, 10:52 AM
#4
Originally Posted by blackandwhite
1. I have an exhaust leak, probably in the front manifold. I am replacing the gaskets and studs this weekend.
This problem is most likely the majority of your bad gas mileage problem...
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