Lean puzzle

[dguy]

Kitten's car likes to play with my mind.   

When driven at a sustained RPM of about 3,250 or higher, it will occasionally whine about an excessive lean condition being picked up by the O₂ sensor.  Reducing speed to 3,000rpm (or less)always remedys the situation within a few seconds.

...and it's totally intermittent.  Sometimes she'll complain within a few seconds of running that fast, other times she'll comfortably cruise along without missing a beat.


My first thought was an intermittent open circuit or corroded connections between the O₂ sensor & the ECU.  Strike 1.

Next was a tired fuel pump which couldn't deliver the volume needed under load & high RPM.  Strike 2.

In progress, is a hunt for vacuum leaks.


Anyone else have any suggestions before this repeated bashing of my head against solid objects causes permanent scarring?

[2ML67]

Had a similar problem once was vacuum line at cruise control canister, also replace fuel filter they can clog up pretty good. I still say best way to fix is to swap in a bigger engine. HEE HEE Dan

[Kitten]

I still say best way to fix is to swap in a bigger engine. HEE HEE Dan

no no no no no.... I'm not ready to do that yet 

[dguy]

Had a similar problem once was vacuum line at cruise control canister, also replace fuel filter they can clog up pretty good. I still say best way to fix is to swap in a bigger engine. HEE HEE Dan

D'oh ...  nice catch on the fuel filter.  Thanks.

As for a bigger engine... eventually she'll get one.  But mine first.   

[GoFast85]

Had a strange experience last week. About 100 meters from my home I heard a wining noise coming from the enging compartment. Supercharger acting up or what, I thought?. Parked the car and the engine idle went up and down and the engine died. Did I forget to check the oil, or not notice the engine falling out?? Started it back up about and hour later and got about 1100 meters and it died. Cruised into the gas station that was handy just in case I had to tow it back home. Looked a the gas guage and was over 1/4. Decided to put $10 in just in case. Car ran like a charm after I put fuel into it. Moral of the story?? Check the EASY things out first!!

[2ML67]

Those engines shut them selves down when fuel pressure is too low due to either bad parts or low fuel. Does save the engine though when something goes wrong. Dan

[GoFast85]

when something goes wrong

Does running out of fuel constitute operator error 

[2ML67]

I think it falls into the either the oops or the oh crap categorie. Dan

[FieroDough]

check for the EGR stuck open. you can be taking in excessive exaust gas at higher RPM.

Cheers!
Eric

[Kitten]

Well we replaced the fuel filter and the check engine light hasn't given us the lean warning since.... and it's also not complaining as much when it hasn't warmed up enough either, which is a nice side effect

[aaron88]

Vacuum leak?  Haven’t you learned yet.

Step one: attach hose
Step two: clean carpets
Step three: enjoy the free advice

Aaron

.

[dguy]

Vacuum leak?  Haven’t you learned yet.

Step one: attach hose
Step two: clean carpets
Step three: enjoy the free advice

You need help.