Limp mode 4.0

[Shturman]

My 4.0 feels like it is in limp mode, it’s a 4.0 manual swap and I did lifters in it and it starts and idles what seems okay but it’ll jump up and then shut off, but also driving it feels low on power, and will what seems like redline at 2.5k it just stops accelerating and sounds like it’s on redline but it’s only 2.5k, tach is fine and okay but I need some help, could it be not getting fuel correctly or?

 

[Dilligaf1]

Codes? IDK Crank Position Sensor or cam synchro maybe? More data is really needed before anyone could really diagnose anything. Running rich or lean? What was swapped engine, trans, both? Computer correct? Computer caps leaking?

I had a different vehicle that did something similar and it ended up being a cam position sensor. No codes, no power, completely give up at 3.5K. I've also seen VSS cause something similar, ecu was limiting throttle because it thought the vehicle wasn't moving, but I don't think your gen 4 ecu is that smart.

 

[Shturman]

No codes just transmission swapped, can’t really tell if it’s lean or rich but it sometimes will smell rich, right now it’s idling at 1k but will just randomly die, it might be the crank pos but the only thing I did for that was unplugging it

 

[Dilligaf1]

How long ago was the manual swap? Why did you replace the lifters? The issue happen right after the lifter change? I'm not familiar with how to change the lifters on a 4L, did you need to remove the intake?

Might want to pull some of the spark plugs you can get to, color will tell you if it's too rich or lean. 93 has a bank fire injection system, so at least get one on both sides.

 

[Shturman]

I didn’t do the manual swap that was the previous owner, I replaced the lifters becuase one of mine was clicky clacky, to get the lifters out you have to pull the heads off, they are still clacking after startup so it could be they need to bleed air out, I left them in a bath of oil for a day or two before I put them in.

 

[SenorNoob]

After reassembling my 4.0, it made an awful racket for about 15 minutes of run time. I had it in the shop at work and had to move it so just started driving it home. By the time I got home it was silent.

 

[Shturman]

After reassembling my 4.0, it made and awful racket for about 15 minutes of run time. I had it in the shop at work and had to move it so just started driving it home. By the time I got home it was silent.

Yeah right now it seems I have low oil pressure

 

[gaz]

@Shturman
The heads do not need to be removed to change the lifters on the Ford OGV 4.0L, the rest in the heads, not below them. You should be able to remove the lifters after if the:
• valve covers
• rocker arms and rockers
• push rods
There may be other components that need to be moved or removed depending on the engine configuration, EX. EGR and other components that can be in the way.

 

[Shturman]

So just for your information, not trying to be rude here at all I know text tones hard to interpret, the heads do have to come off, trust me I tried to get them out without pulling the heads off the hit the bottom of the heads when trying to pull them out. The pushrod holes don’t have the same width the holes in the block do for the lifters, but the truck doesn’t have oil pressure and I think the pickup screen got clogged with Lucas oil tbh. It was 20 degrees out and a 30ish year master tech I know said he runs 20w-50 and a bottle of Lucas in his ranger and he’s never had a problem and he suggested using it to quiet my lifters but I tried it it did nothing then I starting replacing them and after that I went to start it and it had no oil pressure and I don’t have any way to lift the engine to get the clearance to remove the oil pan so I sent it to a shop

 

[Shran]

Yeah right now it seems I have low oil pressure

I would test this with an aftermarket oil pressure gauge rather than relying on what the factory instrument cluster gauge says. Even fairly low oil pressure at idle (warm) is not a huge deal... the 302 in my crawler will sit at like 10psi at idle after it warms up.

I would not have used 20w50 and Lucas. That is a recipe for destroying an oil pump at cold temps at worst - hard starts and unnecessary wear at best. The best way I have found to deal with sticky lifters is to dump about a quart of diesel fuel into the oil, let it sit & idle for a while, and then change the oil with something like 5w30.

The only time I have found 20w50 to be the right oil was in a racing application where the ambient temp was very high and engine temps were way above normal. We were losing oil pressure on 10w30. The engine was worn out to begin with so that was part of the problem but 20w50 helped a lot. I would suggest taking your friend's advice with a grain of salt if he is telling you to run molasses in your engine at cold temps!

 

[Shturman]

Yeah I’m never listening to him againi had stuck two mechanical pressure gauges and had absolutely zero pressure, so I took it to a shop. the shop dropped the oil pan and found pieces of bearings in it, and it clogged my oil pump so I’m thinking about diesel swapping it, 1.9 tdi or 4bt