Jaguar F-Pace Non Runner
Discussion
I don't have much to add, but even before I read the issues you are having at the end of your post, I did wonder if the changes to the exhaust from the standard capacity, pressure etc would have an impact on running. I know you had the ECU sent off and mapped to take the DPF out of the equation, but as you have modified the DPF, even that may not be accurate to the new parameters you have in terms of flow etc. No substitute for a live map if you are modifying things by hand, just an idea of course.
Not saying it is that as you have also had injector issues, but it's the only non-standard modification you have in the mix at the moment so my money could be on that initially.
Not saying it is that as you have also had injector issues, but it's the only non-standard modification you have in the mix at the moment so my money could be on that initially.
Given how a blocked DPF can kill the turbo i'd be looking at the DPF causing a restriction.
Injectors, you can sometimes get them from euros for a few pence but we always get the bolts and clamps from the main dealer, Bolts are usually stretch and need replacing.
Get a new clamp and gasket from the main dealer aftermarket are poor, you could try and seal it with high temp gasket sealent.
Injectors, you can sometimes get them from euros for a few pence but we always get the bolts and clamps from the main dealer, Bolts are usually stretch and need replacing.
Get a new clamp and gasket from the main dealer aftermarket are poor, you could try and seal it with high temp gasket sealent.
shalmaneser said:
maybe get a second hand dpf and drill a hole through the middle? keeps (some) of the soundproofing and doesn't effect the sealing surfaces but also removes the restriction?
That's not a bad idea. It would require me buying another DPF and I don't want to do that unless I have to as they aren't cheap. stevemcs said:
Given how a blocked DPF can kill the turbo i'd be looking at the DPF causing a restriction.
Injectors, you can sometimes get them from euros for a few pence but we always get the bolts and clamps from the main dealer, Bolts are usually stretch and need replacing.
Get a new clamp and gasket from the main dealer aftermarket are poor, you could try and seal it with high temp gasket sealent.
It does seem like the DPF is causing a restriction, I've made a video of how it is. I spent ages lining up the DPF onto the turbo so it sits nice, I closed the clamp a bit so it's tighter. I'm confident this rules out the leak just being a dodgy gasket, poorly located DPF. As soon as I fire it up you can see it leaking. It wasn't like this previously. Injectors, you can sometimes get them from euros for a few pence but we always get the bolts and clamps from the main dealer, Bolts are usually stretch and need replacing.
Get a new clamp and gasket from the main dealer aftermarket are poor, you could try and seal it with high temp gasket sealent.
I didn't expect it my modification be a problem, it's 2.5" same as the downpipe and it is dished a similar amount to the bottom of the DPF casing is. You'd think it's completely blocked the way it's leaking.
tight fart said:
The pipe that you put through the DPF housing, did you drill holes in it?
I think that would allow some expansion and reduce the pressure.
That makes a bit of sense to me too: I'm in no way qualified to have any opinion really, but it seems to me like the turbo might be pushing against the modified pipe, forcing the DPF away from the turbo & that's causing the gap in the seal? Whatever, good luck with getting it sorted, always amazed at the work you do!I think that would allow some expansion and reduce the pressure.
I didn't drill any holes in it. I think the plan this weekend will be to cut it back open, hack it all apart and leave it how it was before. Fingers crossed I can get it back together properly, it's going to be a lot of effort to cut it out.
I still don't really understand why it's such a problem for the exhaust flow, same diameter pipe and I don't think the merge angle is all that bad. It's leaking lots and it's not even under load in the video.
One thing I need to start doing it one job, then test rather than multiple and end up scratching my head if something isn't how I expected. In retrospect it's mad I didn't fire it up after doing the DPF mods but before doing the injectors.
I still don't really understand why it's such a problem for the exhaust flow, same diameter pipe and I don't think the merge angle is all that bad. It's leaking lots and it's not even under load in the video.
One thing I need to start doing it one job, then test rather than multiple and end up scratching my head if something isn't how I expected. In retrospect it's mad I didn't fire it up after doing the DPF mods but before doing the injectors.
One other thing that crossed my mind, you said it isn't measuring back pressure, or the sensor is mapped out, that in itself with the different flow could be causing you trouble. Before you put the extra pipe inside the DPF there would have been expansion room and reduced back pressure, could be that the ECU isn't even picking up increased back pressure if the sensor is off/mapped out.
I do love modifying cars, weather it be for more power or more convenience like this, but one thing I have always found is, if you change one thing for the better, it almost always throws a spanner in the works of something else.
Hopefully removing the pipe will sort it and improve flow, got my fingers crossed for you.
I do love modifying cars, weather it be for more power or more convenience like this, but one thing I have always found is, if you change one thing for the better, it almost always throws a spanner in the works of something else.
Hopefully removing the pipe will sort it and improve flow, got my fingers crossed for you.
Mikebentley said:
Get the map off it and return it to standard. I know it’s personal choice but I would never buy a car that’s been remapped. Just buy the better model.
OP I am in awe of your work.
Thats not exactly always the case, theres plenty of cars with no 'better model' that are infinitely improved with decent tuning, coming from Defender TD5 land the work Alive do to a TD5 makes the factory tune look prehistoric, combined with their intercooler and hybrid turbo it becomes a modern car. OP I am in awe of your work.
I'm no expert, but years ago (80's) experimented with flow (both inlet and exhaust) and I quickly found I could unwittingly create a restriction when I thought I was improving flow.
Borrowing ECSY's pictures....
Looking at this part of it... Could that concave section be creating some kind of unwanted back pressure, due to the change in airflow?
I'm wondering is this is creating some kind of venturi, but accidentally not speeding up the flow (or causing the flow to speed up in the wrong direction from the exhaust pulses, resulting in excessive back pressure).
This is after all fed from quite a large hole!
I hesitate to wonder if that concave section were made somewhat deeper (the full depth of the DPF) - would that solve the problem?
Methinks a crash course in laminar air flow is needed here lol.
Borrowing ECSY's pictures....
ECSY said:
I cut open the DPF just after the cat (which is still there) and added a pipe inside.
Looking at this part of it... Could that concave section be creating some kind of unwanted back pressure, due to the change in airflow?
I'm wondering is this is creating some kind of venturi, but accidentally not speeding up the flow (or causing the flow to speed up in the wrong direction from the exhaust pulses, resulting in excessive back pressure).
This is after all fed from quite a large hole!
I hesitate to wonder if that concave section were made somewhat deeper (the full depth of the DPF) - would that solve the problem?
Methinks a crash course in laminar air flow is needed here lol.
I spent some time on it this evening. I removed the DPF, then with everything disconnected from it, the EGR pipe, the down pipe, the heat shields, then connected it up to the back of the turbo, started it up and no leaks from that join. That rules out the design of my pipe inside the DPF being the issue (not saying it is perfect). I re-fitted the DPF but this time started with that clamp on the turbo to DPF first and then made everything fit it, the EGR pipe and the clamp on the downpipe that bolts to the gearbox ended up being miles out so I think where the DPF has been welded back together it's slightly off, only takes it to be 1mm out at the top could be a 1cm or more on the piss at the bottom. With all that done it's now much better, there is still a slight puff of smoke when it's rev'd but there's a couple more tweaks I want to make and I'll change the gasket and get a new clamp. I think I'll be able to sort this issue without opening up the DPF again.
Took it on a test drive and somethings not right with it still. It's got a knocking sound when I accelerate, sounds exactly like the injector chuff I had before. I can't feel anything on the injectors themselves at idle and I did spill diesel when I first fitted them so all the injector bores were full and none of them bubbled up. Also it's still not idling nice, it's a bit rough but feels smooth when I drive it. Something isn't right, I think I'm going to have to pull the injectors back out to see if there is a leak or not (which means new bolts and copper washer again).
Really wish I'd not bothered doing anything to it last weekend now. Been off the road a week so far with no end in sight.
Took it on a test drive and somethings not right with it still. It's got a knocking sound when I accelerate, sounds exactly like the injector chuff I had before. I can't feel anything on the injectors themselves at idle and I did spill diesel when I first fitted them so all the injector bores were full and none of them bubbled up. Also it's still not idling nice, it's a bit rough but feels smooth when I drive it. Something isn't right, I think I'm going to have to pull the injectors back out to see if there is a leak or not (which means new bolts and copper washer again).
Really wish I'd not bothered doing anything to it last weekend now. Been off the road a week so far with no end in sight.
Having done a bit of research on the internet, I saw something about if you remove the top part of a diesel injector which has the solenoid the ECU calibration is lost. Not sure how true that is, can't find much else on it.
It also seems fairly common for people with newly fitted injectors to get an injector knock. The ECU re-calibrates the fuel quantity values and the knock goes after some driving. So I guess I just need to drive it and see what happens.
It also seems fairly common for people with newly fitted injectors to get an injector knock. The ECU re-calibrates the fuel quantity values and the knock goes after some driving. So I guess I just need to drive it and see what happens.
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