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I have a known good ECU from my 94 parts car.
Make me an offer please.
I don't get on the computer very often so call or text me @ 650-455-1110
Thanks,
Steve
Hello everybody,
I hope everubody is ok with the lockdown. It's not easy, but we need to have patience.
I still have the same problem.
I didn't answered to the ones who offered their ECU because I already ordened one before. Sorry for that.
But I still have the same problem.
I bought an revised ECU but it didn't work. So I send my ECU to fix it.
I payed a lot of money to fix my ECU in the USA, but the car has the same problems.
I told the guy who fixed it and his answer is that my ECU had a lot of issues and he fixed it. And afterwards he said that the car has other problems than the ECU.
My mecanic says that the ECU is not fixed and that the ECU is the problem. He said he already checked all the other options that can give this problem.( He is quite experienced because he used to work on this model in the 90's in an official Jaguar dealer.)
So, I really don't know what to do. All this costed me already a lot of money.
I live in the north of Spain and I cannot find another good mecanic.
Does somebody knows a mecanic (near the north of Spain) who can help me.
Thanks for informatoin.
Dirk
You never confirmed if the throttle body is clean. It's very easy to check. You don't have to be a mechanic to unscrew a hose clamp and look inside.
I suspect it's either that, or a poorly adjusted TPS.
The only other suggestion I have is the MAF. You can buy a spray cleaner for the sensor, and then, with the engine running, move the wires around that plug into the MAF. It is not uncommon for these wires, or the plug to lose continuity. If you move the wires and harness plug around (again, with the car running with a warmed up engine) and get any sort of RPM change, that could be the cause.
Hi Vee.
I have the car at home.
I suppose my mecanic did all this.
I do not know much about working on my car. But I have a friend who can help me.
But, of course, I have to wait the lockdown. Here in Spain, we can only go outside for urgent things.
I keep you informed.
Thank you for your reaction.
This may help you understand what you're looking at.
I really believe it's most likely a TPS, but here's a picture of your throttle body. If it looks as clean as this one, then you can probably cross it off the list. (Make sure you open the butterfly to make sure its clean inside too!
The TPS is the sensor with the three prongs on the bottom. That sensor figures out what position the butterfly is in. If it is failing, or out of adjustment, the engine will rev high, like yours. You should be able to loosen the two screws holding it in place, allowing you to adjust it. This only works if you can adjust it in place, not removed from the car, with the engine running. You might be able to adjust it yourself! Loosen those two screws just enough to allow you to force the sensor to move. It shouldn't be easy, but it shouldn't be hard either. If you are successful, you'll then tighten the screws, locking it in place. Again, this must be done with everything on the car, with the car running. You cannot do this with the throttle body out of the car.
These are the two screws I'm talking about. Loosen them just enough for you to move the TPS sensor, but not loose enough that the sensor can move around on it's own.
Hi Vee,
My mecanic already controlled the throttle body and the butterfly. It is clean.
I'm looking how to check the TPS.
I keep you informed.
Thanks a lot.
Dirk
The TPS should be reset with a computer with the correct software. It's very simple...but I'm sure no one around you has that.
The only other way, should be to manually rotate the TPS with the engine running. I have bench tested a sensor and it seemed to work fine, but the car did not like it. I was experiencing fuelling issues. One day, I finally bought a new one and it cured my problems!
You will be able to adjust the base idle with that sensor rotated. I'm not sure it will be enough. You may need a new sensor, which may require that computer reset...
The only other thing to check are the wires at the harness. They do get brittle. Move them around, again, with the engine running, to see if it makes any difference. Do the same with the harness at the MAF. Both harnesses can give you trouble.
A couple of things came to mind; there is supposed to be a little fine adjust screw on the housing, on the left of the butterfly(throttle plate). It is supposed to have a seal of potting compound but sometimes you will find it missing and possibly may have been adjusted before or has loosened up and backed out by vibration causing a very low idle and or the throttle plate can stick in the idle/closed position causing a sticky transition to open throttle. I found mine backed out, that's how I know. The other thing that came to mind is the EGR. If the EGR valve poppet does not close fully in the idle position, and stays open or had crud on the seat and never fully closes, you will get an artificer idle, sometime even stalling as there should not be recirculated gas (EGR) at low idle. See attached TSB that talks about it and shows the operation. 1. It should not be commanded open at idle. 2. The commands by the ECU may be correct but if the poppet is held open by a dirty seat, it won't close and seal properly at idle.
Just some things to check
The throttle butterfly should be at 0.002”. The mechanic should be able to check that quickly. I would have assumed that he had checked that already.
If thats the case, there shouldn’t be any reason to adjust that screw.
As for the EGR, it should throw a code if it’s faulty. I have seen that code on my car. I know the car is stingy with codes, but I think this is one of the codes that would pop up.
Vee, I cannot find a similar thread where you explained or showed a diagram of what the inside of the TPS looks like. You mentioned that gas or oil can migrate down the butterfly shaft and down into the TPS wiper/switch area beneath the TB.
The situation for the last several weeks is a no-start or an intermittent start with starting fluid and running fine but when let idle for a few minutes, it just cuts out and will not start again for a while or at least when I try to persuade it with starting fluid again.
Does anybody have a breakdown of the TPS switch mounted on the bottom of the TB? I really don't want to have to remove it to see what it looks like due to possibly not being able to get it back in the original position where I would probably need software to reprogram it.
Thoughts? I'm running out of ideas. Would intermittent TPS cause a no start or hard to start issue or just a high idle or similar?
Last edited by carsnplanes; Sep 13, 2020 at 05:13 PM.
Hello everybody,
First of all thanks a lot for responding.
I didn't do anything to my car lately. But at the end I send it to an Englishman in Allicante, Clasicos Legendarios in Redovan.
This guy, Rob, fixed my car in less than 30 minutes and one new sensor (of the gasoline) of 30 euros !
Next week I will have my precious car back to drive it under the Spanish sun ! I can't wait !!!
Once again, thanks a lot and maybe we talk later in this forum...
For our benefit, ould you let us know exactly what sensor/ part number he replaced?
I'm still onfused that you said the engine still ran when your original mechanic closed off the air intake? I still don't see how that is possible, if you don't have an air leak on the inlet manifold? The engine can't run without air being drawn in somewhere, so sadly I think he must have misled you?
Hello ptjs,
Like I said before I am not a mecanical wonder... I don't know a lot about mecanics.
But I will ask it when I go and get my car next week or the week after.
I live in Malaga and my car is in Allicante. Some 500 kilometers away.
The mecanic in the north of Spain didn't found the problem. It costed me a lot of money for nothing. I sended my module two times to America, a lot of labor hours, a lot of time...I already forgot how much it costed (luckely) but it was more than 3000 euros...
But anyway, now it's fixed and I will enjoy my beloved Jag..
Talk to you later.
