Codes
 

My friends 99 986 Base engine light is on. He took to indie, dropped a grand and light still on. Says it is running lean but can’t locate. Smoked looking for leak.
The codes I’m getting are:
P0300
P0304
P0305
P0306
P1316
P1317
P1318
P1319
All misfire related damaging to CAt and emission relevant. Anyone have any suggestions besides new mechanic. Already there.

Going on just codes with no other information.
Those codes are all on the same cylinder bank so it is unlikely a lean condition.
How old are the plugs and coil packs.?
Have they been looked at or changed since the issue started?
What recent work has been done on it??
How many miles?

Going on just the limited information in your post.
I would suspect an issue with the plugs the coil packs or the wiring to the coil packs.
Those are the three things I would check, test and verify as good before anything else.

Sorry, if I remember correctly the engine light came on. He brought over with a new filter and we plugged a obd on it. 2 codes. Reset the codes, light went off. We drove and the car was having a tough time getting over 2k. We turned off, restarted and went on our merry way running okay. He said car felt it lost a little pep. Brought to shop, didn’t fix, light still on. Didn’t do anything with coils. I plugged my Durametric on tonight and got all these codes. There was 10, I reset drove and 2 vanished when engine light came back on. I can’t use Durametric on car for anything other than codes since enthusiast version. So today we have these codes, engine light on and lost a little power. Also, when I test drove, it sputtered at around 5k once. I couldn’t reproduce the sputter.
Thanks for any help. Considering he just handed over 1200 to have nothing fixed, figured I try here.

Bought car with 90k, now about 95k. Haven’t checked plugs or coils. No receipts. Car has been great up until this point.

With no service history on the car start with the basics.
Plugs, coil packs, and wiring to the coil packs.
Rodents have a habit of chewing wiring so look at and test the wiring from the DME to the coil packs.
Let us know what you find.

Will do. Thank you.

Haven’t gotten around to looking at spark plugs/ coils but he said car is actually running worse than when he brought to shop. Now it is struggling to get over 3k and it made a bang noise when driving. I advised to just shut down and have towed to other shop.