Mazda MX-6 Forum banner
1 - 12 of 12 Posts

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #1 ·
I just got a cel today, pulled the codes and got EGO RICH, I guess that is 02 sensor. My car has been getting really bad mpg, I filled up and have since gotten less than 200 miles and have maybe 1/6 of the tank left.

Im going to replace the 02 sensor but am wonder about a few things. I cleared the memory after pulling the codes and have driven a few miles and have not gotten it again. I wonder if there is more to the running rich than just the 02 sensor.
 

·
Registered
Joined
·
1,640 Posts
The codes are different on earlier cars but on mine a rich condition on deceleration occured because of a problem with the ISC system. Next time you're driving see if you can find a long downhill slope and stay off the gas letting the car decelerate by itself to see if the code pops up again. btw an A/F gauge is extremely helpful in this kind of situation. Do you ever get a high idle @1000 rpm after the car is warmed up?

If you find these symptoms, it may not be the O2 sensor at all. Instead opening and cleaning the ISC valve and air valve on the back of the TB might be helpful.
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #3 ·
No my idle is pretty decent.

On cold start up its at 1.5 after maybe 5 minutes at idle its down to about 775. it usually fluctuated between 750 and 775 depending on wierd stuff like if im facing uphill or downhill or flat. Maybe its just me I dont know.


I had a problem with fuel pressure regulator and replaced it. For psi reading I got about 85 psi from pump and before replacing the regulator it was 85 psi to the injectors. After replacing regulator it says 65 psi to injectors and I know that is about double what it should be But it doesnt seem that bad. Ive gotten bad mileage since Ive had the car.
 

·
Registered
Joined
·
1,247 Posts
not an expert with fuel system at all and am 99% sure it's something to do with the 65 psi at your injector if that is in fact double the normal pressure.

the check engine light comes on for a reason, reseting the ecu does nothing but turn off the lgiht for a while, but this still mean that at soem point in time something was wrong the triggered it so u may want to look into it especially if you know u did not trigger it by some mod u did ect....
 

·
Registered
Joined
·
111 Posts
if you have that much pressure to your injectors. check for a vaccum leak. low vaccum makes the FPR raise the pressure.
 

·
Registered
Joined
·
2,421 Posts
I'm having the same problem lately, at idle my car is a steady bar rich and my rpms are at 1100. This is after the car has warmed up, too. oxygen sensor was replaced last spring, I forget which brand I used. When i push the clutch in, the rpms seem to drop back to normal. No check engine lights are present...should i give the ISC and EGR a cleaning?
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #8 ·
sweet, what is that from?

I have both probe shop manual and haynes. Dont remember seeing that.
 

·
Premium Member
Joined
·
7,327 Posts
TiZBaD99 said:
sweet, what is that from?

I have both probe shop manual and haynes. Dont remember seeing that.
Where do you think it's from? :D

(1991 Mazda MX6/626 Factory Workshop Manual)
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #10 ·
Im still a grasshopper.

I wonder if i didnt look hard enough.

If it isnt in the ford shop manual, then mazda really is better.

Im going to check later

but that looks way to clean to be somthing that you just scanned, do you have it on cd or somthing?

Unless im the only messy one
 
G

·
Heh, Majik scanned from the MAZDA shop manual, not the Haynes pile-o-crap.

This thing is the MX-6 Bible and it makes the Haynes manuals look like someones drunken scribbles in the liner of a Gideon bible.

About $70 from a Mazda Dealer, or you can see them on e-bay occasionally for $15-20
 

·
Registered
Joined
·
1,719 Posts
Discussion Starter · #12 ·
I know the difference I have the ford shop manual. Comparing it to the haynes is like comparing an essay to an outline.
 
1 - 12 of 12 Posts
Top