Thank you for the help.

Guess I’ll replace the gaskets, though it doesn’t sound fun. I only recently discovered where to get oem parts without breaking the bank, so I’ll use the fel pro ones. This is my first car and still learning how to fix it.

on the topic of fairly easy and cheap things that might help, would fuel system cleaner hurt? Not something I’ve used before, but some seem to regularly.

thank you again

I've only seldom used it. Generally, I don't see a need.

Just don't get your gas at the worst dump in town and you'll probably be good. I've seen so many cars pass 200,000 or 250,000 miles with no fuel-related issues that I don't see it as a necessity.

New Felpro gaskets installed, and that doesn’t seem to have helped. The old ones weren’t original, they were the blue ones. Still probably wasn’t a bad idea. At some point some mice must have been living in there.

But after I disconnected the battery and drove for a bit LTFTs were creeping back up.

warm and at idle, they were averaging 7-10% when I started accelerating they drop a bit for a second but then move around 10-14%. While coasting down hill they would go as high as 18%. When decelerating the opposite would happen. As soon as I let off the accelerator they went up to usually 16-18%, then drop to 10-14%, just before coming to a stop sometimes they would drop as low as below 10% before settling at 7-10% at idle.

Seems backwards of what most vacuum leaks are. Not sure yet where to go from here. All the data the MAF is sending seems ok I think

thank you,
Edward

Are there still misfires?

it hasn’t thrown a misfire code since like November. There was a greasy layer of oil in the intake, but it didn’t seem overwhelming. The PCV is the unserviceable kind unfortunately so not really sure what I could do about it anyway. I didn’t find any other obvious vacuum leaks. I also tried listening to the injectors with a stethoscope and I think they sounded normal.

thanks for all your help.
Edward

Forgot to mention. I also tried unplugging the MAF while idling when about half warm. It’* stuttered but didn’t stall and had no effect on the fuel trims.

Like zero effect?

Did it light up the check engine light?

Ok redid the MAF unplug test just to be sure. Still didn’t stall, though from the sound of it the rpms took a dive for a split second. It sounded a little off at idle but terrible. Maybe I didn’t wait long enough last time but it did affect the trim numbers this time. It also threw a po102 I think.

At idle without MAF
fuel system 1 closed
fuel system 2 closed
cal load value 3.5
STFT B 1 -1.6%
LTFT B 1 6.3%
STFT B2 2.3%
LTFT B2 2.3%
MAP 11 inhg
rpm 551
vehicle speed 0
ignition timing advance cyl #1 19.5 degrees
intake air temp -38 degrees
air flow rate from MAF 0.13
throttle position 0%

I know the unplug the MAF sensor isn’t guaranteed to work. Though not having a brake booster may help. I’m a little confused as to how the air flow rate from the MAF could even show a low number.

should I look into a new MAF perhaps? Any recommendations on brand?

thank you again you e been so much help,
Edward

Trims numbers are a lot smaller.

I would change it to a Delphi unit.

New Delphi MAF has been installed and it’* still lean, but maybe slightly less so.

the new sensor does seem to have helped, it’* not quite as lean as it used to be. LTFT are usually between 10-15%, lowest when accelerating from a stop, sometimes 7-8%, and highest when maintaining about 35-45 mph, at about 15%. At idle about 11-12%or so. The biggest difference is when I start coasting it no longer jumps 5-15%, now only maybe 2%. Everything else on the live data looks fine except the downstream o2 sensors are both still reading 99.2%.

not sure where I’ll do from here, I guess recheck for vacuum leaks maybe?

Edward