[dantheman76]

I recently have experienced a severe drop in mpg. From 19 mixed to 14. This happened before moving to Texas from Utah. I have dropped about 4000 feet in altitude.

I read in some threads about the ethanol and my next tank will be with it if I can find a gas station out here that doesn't use it. I have no indicator lights on. It seem to start when my change oil/service needed light came on the odometer screen. I changed the oil and reset. But seems to have less zip. Tire pressure is good.

What suggestions do you have for me.

Thanks

 

[Buffalo4]

What year is it?
How many miles are on it?
Should have quite a bit more zip at the lower altitude.
Have you ever had the valves adjusted?
Does it just lack power,or is it running a little rough?
If it's running a little rougher, it could be a spark plug coil.
Is the air cleaner still good?
Does it idle ok?
With more info, you will have a better chance of a solution.
Buffalo4

 

[dantheman76]

Ok sorry should have given more info. It is an 02 with 150k. No idea on valves but no noticible sounds from valve train.

It does run a little rough and seems to hesitate a little. Has new air cleaner and new plugs.

How would I find which coil is going bad if no check engine light?

 

[Buffalo4]

It seems that the exhaust valves clearances actually get tighter. This is because they sink in their valve seats some and therefore decrease the clearance and hence, get quieter.
If that could be your problem, please adjust them as, failing to do so could be expensive.
Still the big drop in mpg when you went to a lower elevation is unexpected.
If it's a coil, you can check by disconnecting the low voltage connector on the coil when the engine is idling and see if it makes a difference. If it doesn't, it 'indicates' a bad coil. You can switch coils with the one next to it and see if that cylinder now seems to do the same.
A good compression test can help a lot when trying to diagnose your problem(s).

Buffalo4
PS: Please post back if you find the solution. I have a 2003 with around 130k miles on it.

 

[dantheman76]

Do you happen to know the valve speck? I can check that pretty easy.

 

[Buffalo4]

Sorry, I don't but you can probably do a search on it in this forum or on Google. I did it on my friend's 2000CRV and it is recommended to set the valve clearances at the loosest setting (biggest gap).
I believe there is probably a tutorial on doing this on this forum, step by step with all the specs.
Buffalo4

 

[rjcmstar]

I recently have experienced a severe drop in mpg. From 19 mixed to 14. This happened before moving to Texas from Utah. I have dropped about 4000 feet in altitude.
Thanks

Given that you just moved, I would suspect you are in a
more populated area with more cars and traffic lights. More
stop and go implies a significant drop in fuel economy for
a heavy minivan. Depending on what % of mixed is in the
city, 14 isn't unexpected (check Wild Willy's postings for
example).

 

[liem0112]

Same problem

My car is same thing. It is only about 14-15 mpg. And it run very rough not smooth. My is 1999 and has 146000 miles on it. No check engine light. The only thing I didn't check the coil. Can you guy explain more how to check the coil.
Thanks