1997 lean condition

[crowncrazy87]

1997 model with 4.6. Running extremely rough, no power, pinging. Shows lean code for both banks but no actual misfire code. I've checked all vacuum lines, intake gaskets, pcv valves, fuel pressure. Full tune up with plugs, wires, fuel filter, air filter, cleaned MAF.

I did have it running and one by one pulled injector connectors. Some made a difference in running others not so much. Clogged injectors? I did check resistance on them and all were almost identical readings and you can hear them all clicking.

Just kind of at a loss here on what to check or do next.

Just bought this rig and want to get it right!

 

[Killer Ride]

Have you checked the Cops or the O'2 sensors? How bout fuel trims?

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[crowncrazy87]

97 4.6 doesn't have COP set up. Has the two coil packs each with 4 wires. I can check the fuel trims. Where should they be running at?

 

[Killer Ride]

Sorry bout that I would check the 2 coil packs then and the O'2 sensors. There's 4 02's right? I actually like it better than 8 Cops but a little less tunable. The trim levels don't run at a set level they are constantly changing but you want to look for vast differences from bank to bank and also from long term to short term. For '97 I would buy 1 of each the upper and the lower then you could swap them out to troubleshoot which side it is. They are different so make sure Ther is an upstream and a downstream. Usually there is 1 lazy one that responds but not as quick as it should.With it being 22yrs old I would probably replace both sides or when I could afford it. They are not too bad at Rockauto.com.

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[crowncrazy87]

I got some good o2 sensors on my currently down (fuel pump) 98 f150 4.6. I could borrow those first and see what happens. Heck I could borrow a lot of stuff to help trouble shoot lmao

 

[Killer Ride]

There you go, now your cooking! I would do exactly the same thing. Why buy to troubleshoot? Good luck

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[Killer Ride]

Post back up here if you figure it out

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[TobyU]

I don't think it's young to be O2 sensors. You could cut the wires off all 4 and it would still run pretty well.
Both banks lean points to vacuum leak. The intake manifold likes to learn on these. Try some spray around it... Carb cleaner wd-40 etc to see if it smoothes out when liquid hits leak.
Try the cylinder cancelling out with the spark plug wires. Use a rag or glove and pull one up one at a time to see the difference.
All should make a solid miss. Sometimes you will get one that as soon as you connect it, it fires smoothly for about 2 seconds then back to missing. This can be cool pack or wire. On COPs it's a weak one.

 

[1955moose]

2 things on top of what Toby said, I'd actually smoke the Motor rather than spraying it for intake leaks. Also look for smoke coming out leaking exaust manifolds. 02 sensors actually last a long time, the wires get damaged is the biggest problem with them. Do the other tests before swapping the ones from your F150. If you do remove the known good ones, from your pickup, don't touch the tip that reads info with a greasy hand. Their like halogen bulbs, they don't like human fingers touching them. As far as fuel trim readings, theirs charts online. Theirs short term, and long term readings. When reading these you ideally want to see close to 0, but they fluctuate a little plus or minus. When you have a intake leak or malfunctioning cat or 02, that's when the readings are way off. You will need Forscan or a reader that can do fuel trims. The cheaper ones only usually do codes. Let us know what you come up with.

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[Killer Ride]

I forgot to ask but if you have stock exhaust it could be same issue I'm having with clogged Cats. On my '98 Expy that I bought a few months ago it had no power. And when I would gas it over half way it would make a sound like air escaping a compressor. I took it to an exhaust guy and had him back pressure test it sure enough that's what it was. This isn't my 1st time dealing with the same issues as you I also have an F150 I installed a '02 Lightning motor/trans in and I was getting random lean codes on both banks, again it was clogged Cats. Drove around for 7months before I figured it out.

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