Unplug the VSS and report back. Could also be water ingress to ECU or failing plug to coil pack.
D1 rev limit around 2k rpm
- Thread starter NigelDI
- Start date
Again….long distance. What is he smelling? Sulfur? Raw fuel? But has fuel psi? Fixing cars long distance is like pushing water up hill. I just asked for the tps voltage? Rob’s probably right about this not being advanced evaps, that sent my theory to the shitter if he’s right. So if that’s the case what about restricted exhaust?
I’m not thinking crank sensor because I think that would be cutting out and jerky misfiring or just stalls and won’t restart. He’s describing a steady smooth no power kind of deal.
I would have my fuel pressure gauge taped to my windshield on this car for sure. It could have fuel pressure at idle but under load not be able to produce enough volume to maintain pressure. What about the fuel filter?
I would have my fuel pressure gauge taped to my windshield on this car for sure. It could have fuel pressure at idle but under load not be able to produce enough volume to maintain pressure. What about the fuel filter?
Shortly before the reluctor ring completely fell off my Disco's flywheel, it did appear to be short in power going to high RPM. It did set off some misfire codes, IIRC.
When I've seen those it usually runs great right up to about 70 mph and then the engine management does whatever it does to slow you down. When cars do that they don't usually store a code cause it shut the shit down on purpose. So when its a VSS it usually runs great till it doesn't. If I'm following this correctly, he says its always flat, no power ever. With no codes. Theres just not tha`t many things that can do that. A MAF or a MAP sensor can do that. Because it's one of those signals it really can't do a readiness test on. It has to trust the reading till it gets outside of a set window of wrong.
The water in the ECU does act just like that. But usually codes get stored with that too.
Random misfire like the OP has.
But regardless, I think we’re all just trying to give him good suggestions based on limited information. And different suggestions don’t me anybody is right or anybody is wrong. Just means we’ve all had different experiences that are worth mentioning.
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I think this is more of a crank walk case - with some push-back from the transmission, the crank walks forward a bit, enough for the CkPS signal to fade away with increase in RPM. It should trigger a CEL with some codes, though.
When I bought my XD it acted all sorts of weird, wouldn't idle, couldn't use the AC or it would flat out just stall going down the road, couldn't hardly connect any OBD2 device, but when the VSS was unplugged it didn't stall, and it idled decently. Crawl under it and just plug the VSS back in and it would either stall out or start running rough. When an OBD2 would connect it showed no misfires or any faults. I swapped a handful of parts with zero change and finally removed the ECU to inspect it. I removed the covers and immediately I saw my problem. The PCB was very badly corroded on one of the main terminals. I got my hands on another non AEL ECU and it's been running like a champ since. CPS wiring can certainly make them do odd things as well as the insulation just seems to crumble leaving the wires to touch or ground out.
I think Nigel needs to give some more information before anything can move forward.
* Based off of everyones input
- Is the truck advanced evap
- Is the 2k rpm limit violent or smooth
- Check the TPS wiring, sensor and throttle plate
- Check the Crank position sensor, wiring and reluctor ring teeth
- Check fuel pressure driving down the road
* Based off of everyones input
- Is the truck advanced evap
- Is the 2k rpm limit violent or smooth
- Check the TPS wiring, sensor and throttle plate
- Check the Crank position sensor, wiring and reluctor ring teeth
- Check fuel pressure driving down the road
I agree with Best 4x4, Could the ECU you swapped out be faulty? Will it run with MAF disconnected? Had the same problem ended up being the ECU burned after 23yrs of service.
I pulled the y pipe down and theres no difference. It's not an advanced evap truck. And I'm getting raw fuel smell, with good fuel pressure. I haven't checked the crank sensor wires due to being out of town I get back to the truck on Monday though.
It's not steady and smooth its violent truck surges and backfires but wont go over 2k rpm
I pulled the cover off the front of the transmission to look at the flex plate. Upon inspection the ring that rivets to the flywheel has come loose on the rivets, it's still intact but jumps around. Is it easier to pull the engine or transmission to change the flex plate? And do you have any reccomended upgrades for the flex plate?
Thank you all so much for the assistance you have provided!!
Thank you all so much for the assistance you have provided!!
Bam - likely this is your culprit.
Before you go to town with transmission or engine removal, look closer - if you remove the engine oil pan, you may be able to re-rivet the reluctor ring to the flywheel.
Before you go to town with transmission or engine removal, look closer - if you remove the engine oil pan, you may be able to re-rivet the reluctor ring to the flywheel.