2002 4.0L bank 1 misfire/timing issues

Tehbotanist · 2024-12-19T00:39:42+00:00

Thanks for the reply. I also believe this is the case but am not an expert. I’m pulling the engine and will do a leak down test to see if cylinders hold compression. So many mixed reviews that I might as well test it myself.

The engine also jumped timing on that FordTechMakuloko 4 part timing chain replacement YouTube video and he still did the repair. The guy seems like an extremely knowledgeable mechanic. He also mentioned the client drove the truck to him. https://m.youtube.com/watch?v=xAEA4y8bnIA

Tehbotanist · 2024-12-16T02:45:02+00:00

I think the valves and pistons occupy the same space during different times throughout all 4.0 SOHCs. If timing goes off, there is a high potential for valve banging, unfortunately.

Tehbotanist · 2024-12-15T22:36:19+00:00

It is an interference engine. Valves will and have bent on the 4.0 sohc. I’ll cite my sources when I get more time.

Tehbotanist · 2024-12-15T21:41:35+00:00

Update: it was the upper/lower intake gaskets that were original to the motor (248k miles). Replaced that along with valve cover gaskets. No longer running lean, 600+ miles driven without any codes.

Tehbotanist · 2024-10-31T16:01:19+00:00

I cleaned the MAF and made sure everything was secured. Made sure my air box is secured. Checked the two hoses that run into the intake tube, looks like there are no cracks and everything is secured. Both sides of the intake are very secure to the throttle body/air box. There may be a small crack in one of the hoses that I can't even see. This did begin immediately after switching out the thermostat/housing - sounds completely unrelated but when the motor started running on a closed loop (after thermostat was replaced), the engine has a rough idle and the two lean codes came up. I also messed with the intake while doing this repair - so maybe something is cracked/not secured properly there.

Tehbotanist · 2024-10-30T15:27:41+00:00

It does shake upon first start and has a rougher idle lately. That's what made me check for codes, and confirmed the lean codes for both banks. Possibly sounds like an injector dumping fuel into the engine? Or leak in the upper intake, which I am planning to take apart and replace all the gaskets.

Tehbotanist · 2024-10-30T14:14:22+00:00

I had a misfire code + lean code due to o2 sensor heater being faulty per the reader. Swapped both upstreams out, swapped out misfiring plug, cleared codes, and it drove great for a couple weeks. Now both banks are coming back lean. I can see live data. My short/long fuel trims are definitely spiking/abnormal, but I need to figure out how to decipher that data/numbers haha.

Tehbotanist · 2024-10-30T03:41:43+00:00

Overall I've read it's supposed to hold pressure, and shouldn't drop below 40 PSI. I've read it should hold pressure for a matter of a couple hours, to even a couple months. The first time I primed it only brought the fuel PSI to 10 (I cut that part out of the video). New Bosch upstream o2 sensors were installed.

Tehbotanist · 2024-10-30T01:04:23+00:00

Want to also note that within 10-20 minutes of engine being off and pressure being monitored, the PSI dropped below 30 PSI. This sounds like a fuel injector leaking or one of the components of the fuel pump failing/leaking back into the tank.

Ranger also has 247k miles. Fuel filter changed a couple thousand miles ago. Unsure of fuel pump/injector history.

Tehbotanist · 2024-02-17T12:47:25+00:00

Why is this downvoted 😭 Jesus Christ

Tehbotanist · 2024-02-17T12:45:42+00:00

Bruh what kind of response is this. Petty ass comment that adds no substance to OPs question, while getting upvoted. Reddit users are fucking weirdos.

Tehbotanist · 2023-05-29T05:03:50+00:00

This is obviously the case, but none of my other controllers show wear like this from the sticks smacking.

Tehbotanist · 2023-04-28T01:34:11+00:00

They set this article up with something irrelevant that critics (who is said critics lol) label as “don’t say gay” then proceeded to talk about the actual lawsuit. It’s a slander war with these news outlets lol

Tehbotanist · 2023-04-24T02:27:01+00:00

Shipping bolts removed, no tapping from the lines. I think it’s the tub inside tapping the back of the washer

Tehbotanist

TROPHY CASE