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Metered the tps earlier. Instantly I got .38v really smooth all the way up and down. Every time I got the throttle back to closed it went down to .28v. Real smooth volts open to close though. I let the car idle a bit today and it was really nice but is soon as I started giving it some gas it wants to die. I took a video that I will upload. A quick inspection in the trunk shows me that I'm not real smart and all the work I did with the fuel system, I decided to put the old fuel filter back in. I will upload the video later
The TPS sole purpose in life in the V12 XJS is acceleration enrichment, if it is set too low the ECU will not provide enough fuel when you stab the throttle. Engine load is provided by the MAP sensor.
The TPS sole purpose in life in the V12 XJS is acceleration enrichment, if it is set too low the ECU will not provide enough fuel when you stab the throttle. Engine load is provided by the MAP sensor.
if anything is it better to have a little bit too high of a reading than too low? I've never adjusted a tps before. I read how to adjust it, just wondering how touchy it is and if you can get it in the sweet spot easily?
You will need to take your time, slow down, be pedantic, did I say SLOW DOWN.
Rush this bit, and the engine will NEVER be right.
It MUST be between the 0.32 and 0.36 setting. Outside this will have the ECU NOT dropping into idle fuel map, and then the "off idle" enrichment Warren mentioned, is not as needed.
Of course, the Fuel enrichment vac valve MUST also be working, or the engine is trying to accelerate on a too lean mixture.
You will need to take your time, slow down, be pedantic, did I say SLOW DOWN.
Rush this bit, and the engine will NEVER be right.
It MUST be between the 0.32 and 0.36 setting. Outside this will have the ECU NOT dropping into idle fuel map, and then the "off idle" enrichment Warren mentioned, is not as needed.
Of course, the Fuel enrichment vac valve MUST also be working, or the engine is trying to accelerate on a too lean mixture.
Well it's set... and I stuck my older(newer) fpr on. It idles really nice but you touch the throttle and it does not enjoy. Spits out smoke and burbles like mad.
What is the timing set at, as said before, you should start at 10deg BTDC static. Then trim it once the engine is HOT by drive timing is, See the attached Doco.
Are the throttle rods set as per that previous doco, if not, please do so.
Is the fuel fresh?
The engine has had a LOT of starting issues, and will take time to clean itself out, and the longer it can run, and run as best it can, the better.
ALL the silly settings of sensors, including TPS (done), and the throttle discs, and rods, spark plug gap, timing, etc need to be carefully established. It is nearly always a backup of little things that makes a monster of it.
What is the timing set at, as said before, you should start at 10deg BTDC static. Then trim it once the engine is HOT by drive timing is, See the attached Doco.
Are the throttle rods set as per that previous doco, if not, please do so.
Is the fuel fresh?
The engine has had a LOT of starting issues, and will take time to clean itself out, and the longer it can run, and run as best it can, the better.
ALL the silly settings of sensors, including TPS (done), and the throttle discs, and rods, spark plug gap, timing, etc need to be carefully established. It is nearly always a backup of little things that makes a monster of it.
Thank you grant for you time and help.
im not sure what the timing is at... like I said before I need to get the beast backed up so I can get under the front of it. I haven't done timing since high school auto tech another "new" experience ahead(do you have a good document for that?) oh is that one of the documents you posted? The first 2 you posted do not work correctly. I didn't get to do the throttle rods yet. I picked up a new fuel filter today that's going to go in. The fuel is fresh within a couple months after I redid the tank. I put a bottle or 2 of heet in it awhile back and that seemed to get it started before I tore it all apart? I think there was leftover moisture in the tank. Then I read heet can pull in moisture as well. I haven't gotten to deal with the aav as it only runs a couple mins before I try to give it some gas and dies. I haven't gotten to test the fuel pressure either yet. If I were to say anything the fuel pump doesn't seem to run as loud as before...maybe it's slowly dying. It sucks having your project car a half an hour away! Car is so close to driveable but it's driving me nuts right now... V12 Lucas has really been teaching me and frustrating me.
should I just let it idle as long as I can in the condition it's acting? Seems pleasant at idle. Not sure if it's pinging or running on 8 cylinders etc.
If thats all you can do, so be it, not my #1 idea.
If its NOT on 12 cylinders, sort that out, it will reek havoc if its not on 12.
You need to get a plan, write it down, work to it, ONE area at a time.
Its 30 years old, and I guarantee its a tired neglected V12 at best. Wiring will be well past its use by date, and short cuts here will cause other damage.
Same goes for hoses, coolant/fuel/vac, they will need replacing, and I do mean ALL.
The ones I have resurrected over the years, have been no different from what I believe yours is. Most took several weeks of constant work, knowing the V12 is just fine, they always are, its the add on stuff thats toast.
My '85 was 11 years old when I got it, and had spot on service records, and still being used semi regularly, but it needed the works as above, and I did it all before I put it into the Daily Driver fleet, and is just as reliable as any other car.
Took 2 months, including rear brakes, and cradle refresh, front suspension rebushed, engine bay rewired 100%, cooling system rebuilt with Efans.
I have not revisited any of those areas since and it is now 200K kms down the track.
Replaced the filter today I think it was fine 🤦🏻*♂️
Started it and idled real nice again... after a couple mins the idle started to rise so I twisted the throttle a bit. It reved up real nice a couple times and then died. Once it dies I can usually get it started up a couple more times but then it doesn't want to start again once "warmed". I screwed the aav in a bit but prob not enough. It seems like it was out quite far
Super nice to open the hood and find out a family of chipmunks have decided to call your freshly done engine home. I even smacked one in the *** cause it didn't want to leave. They've all been trapped and transported. I wish they would've figured out what was wrong with it while they were in there.
Replaced the filter today I think it was fine 🤦🏻*♂️
Started it and idled real nice again... after a couple mins the idle started to rise so I twisted the throttle a bit. It reved up real nice a couple times and then died. Once it dies I can usually get it started up a couple more times but then it doesn't want to start again once "warmed". I screwed the aav in a bit but prob not enough. It seems like it was out quite far
btw is this ethenal separation or water? Either way how can I get this crap mixed up and burned out? This might be my whole problem. Cars trying to run on water..
Drain it from the swirl tank / sump. There's a bung you can remove from underneath the car. Then I'd pull the return line, add a gallon of fresh gas and run out everything in the lines.
Likely to have some corrosion in both tanks. Check the sump filter and probably plan to pull the main tank to check it.
Drain it from the swirl tank / sump. There's a bung you can remove from underneath the car. Then I'd pull the return line, add a gallon of fresh gas and run out everything in the lines.
Likely to have some corrosion in both tanks. Check the sump filter and probably plan to pull the main tank to check it.
i pulled the tank in spring and cleaned it out(and ground down the rivet and patched some what I thought were holes) and the sump I cleaned out. I'm wondering if there was leftover water from cleaning or if the heet I put in the tank absorbed it... I used heet to get it started before because I think there was some leftover water. Ugh prob the reason it won't stay running now.
Ok pulled the return line off today and ran the fuel pump.. good amount of gas came out... so pump seems ok. Am I getting too much fuel? The fact it idles and if I give it gas it dies... then won't restart. Is it getting flooded? Does anyone have a pressure testing diagram? I know you have to build your own because of the fittings?
Just "Tee" it in anywhere you like between the two FPRs. This will give you a reading of what the injectors are seeing.
High fuel pressure would not be my suspect for stalling when the throttle is opened. Some obstruction in the supply to the pump or a weak pump would be.
Just "Tee" it in anywhere you like between the two FPRs. This will give you a reading of what the injectors are seeing.
High fuel pressure would not be my suspect for stalling when the throttle is opened. Some obstruction in the supply to the pump or a weak pump would be.
filter is new... might just get a new pump, probably needs one anyway. Seems like it must be flooding though if it doesn't want to restart for an hour.
