S2 Not Starting/Not Fueling

S2 Not Starting/Not Fueling

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abercoms

Original Poster:

50 posts

237 months

Friday 27th November 2020
quotequote all
So in my previous post https://www.pistonheads.com/gassing/topic.asp?h=0&... as I started to work out why the previously starting on the button engine was refusing to fire, with lots of help here Ive worked through all the options I can see and tested what I can test, tonight I sprayed Engine start and the engine fired and ran as best it can on engine start, I therefore assume I have proved the basics. Ive also found the diagnostics port which showns no errors, Its a Draper Fault code reader so maybe not best, Im now left with the dry plugs, Im now confident that no fuel is going through injectors, so is it signal or fuel, I thought that putting a voltmeter across injector pins and seeing pulsing 12V showed that I had signal, Im now not so sure as I think there should be constant 12V on each pin, should I test each pin to earth or across pins, advice on definate test appreciated, Ive put 12V onto the injectors I can reach, they click, I also suspect that fuel may have gone into cylinder as next turn of key gave a cough maybe. I also tested fuel pressure by putting finger over pipe and having it pushed off whilst pump ran continuously, again am I correct. Ive read heaps of threads and tried heaps of things.
I make no bones that my experience is based on previous to EFI technology and its 20 odd years since I worked on cars so I really appreciate all your experience
Ta
dave

GreenV8S

30,482 posts

291 months

Friday 27th November 2020
quotequote all
You should have an ignition switched 12V supply on one side of the injectors, and the other side should be pulled down to ground through the ECU when the injector operates.

You can get NOID diagnostic lamps which connect in place of the injector and flash when the injector is fired, to confirm it's being driven electrically. I mentioned on the other thread how to confirm its working mechanically and passing fuel.

abercoms

Original Poster:

50 posts

237 months

Friday 27th November 2020
quotequote all
Well Im mystifyed, managed to borrow a NOID, Ive check the 3 easy to reach injectors, they all plashing as I crank motor, rereading your post in my previous thread, only thing I dont think Ive done is to put a pressure guage on the fuel rail, what sort of pressure guage and do you mean onto the bleed valve on the rail, sorry to sound thick but I obviously am on this ta dave

mentall

469 posts

137 months

Friday 27th November 2020
quotequote all
I bought my gauge on eBay: not very expensive. Yes, they fit on the valve on the fuel rail, just like the tyre pump at the petrol station.

Tell us roughly where in the country you are: someone will happily lend you one.

I found that mine had a non-return valve so the indicated pressure was retained (ie didn't drop when the injectors fired). I removed the innards of the valve so that the gauge responded downwards as well as upwards.

I'll say again: take off the pipe feeding the fuel rail, put it in a bucket, and make sure you've got plenty of flow as well as pressure!

abercoms

Original Poster:

50 posts

237 months

Friday 27th November 2020
quotequote all
Im in the north of scotland, again sorry for thickness but could you maybe post me a link to a suitable guage on ebay all I see are things Id worry about putting onto the valve due to petrol spewing out.
Theres definately flow, if it was beer going into my mouth Id be happy with it, I also had pressure that pushed my finger off the pipe with the pump running continuously and the relay bridged out
ta dave

Penelope Stopit

11,209 posts

116 months

Friday 27th November 2020
quotequote all
Try blocking the return pipe that goes from the fuel pressure regulator to the tank

A stuck open more than an internal leak in the fuel pressure regulator will prevent fuel pressure at the injectors as the fuel would be free flowing straight through the fuel lines, meaning out of and straight back into the tank



A touch off topic but something else to consider for later or possibly now

Am guessing that there's fresh fuel in the tank

phillpot

17,279 posts

190 months

Friday 27th November 2020
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mentall

469 posts

137 months

Friday 27th November 2020
quotequote all
Here's a Chinese gauge for a tenner.

It doesn't specifically say it has a Schrader adaptor, but the one on the end of the flex pipe on the gauge looks right.
The one I bought was just the same, and it did have the adaptor. If it hadn't I was ready to use the adaptor of an old foot pump.

But mine has a manual pressure release valve and tube, and this one doesn't. That may be better, as the gauge will follow the pressure up and down. And it also means that when you remove it from the fuel rail the fuel in the gauge tube will spray out: careful and keep safe!

PS is absolutely right. The official flow test is to measure the fuel flowing out of the regulator so you're measuring flow at regulator pressure. But to do it you need to fit a temporary rubber tube from the regulator to the bucket.

And yes: if the car's been off the road for ages, you may be trying to start it with the water that's got into the bottom of the tank. And there's a theory that petrol loses its volatile components over a long period. One of the (many) things I tried when I was in your situation was to drain every bit of fuel from the tank and put some new stuff in. You can drain the last bit using the fuel pump and the bucket! You can only drain the fuel rail by taking it off the engine: a PITA!

The trouble is, I don't know which of the things I tried made it work. I do know that the major problem was the filter/pump blockage, but yours may be different.

Good luck. It's best that these things happen in winter and in lockdown!




abercoms

Original Poster:

50 posts

237 months

Saturday 5th December 2020
quotequote all
So have I finally cracked it? Ive waited for my £10 pressure guage to arrive, stuck it on pump side and I get a healthy 3 bar as suggested, then remembered about putting on the return side of the regulator which I have done on the outlet/return to tank side, no pressure at all, does that say its faulty or am I just hoping....
Id tried putting mole grips on this same outlet pipe but it made no difference and I moved on, can the thing be faulty that test doesnt work? Is there a means of taking the regulator out of equation to properly test this?
The alternative list suggests replacement and a Bosch number that I think is NLA, the TVR parts replacement suggests S2 but doesnt looks different but the burton power one looks right what would I be best to do smile
Ta dave

GreenV8S

30,482 posts

291 months

Sunday 6th December 2020
quotequote all
abercoms said:
putting on the return side of the regulator which I have done on the outlet/return to tank side, no pressure at all
Perfectly normal, and I don't see any purpose to doing that. What you're looking for downstream of the regulator is flow, not pressure. You won't see any pressure since it dumps straight into the tank.

If you blocked off the return line then all you're seeing is the stall pressure of the pump - which is not useful to know.

abercoms

Original Poster:

50 posts

237 months

Tuesday 8th December 2020
quotequote all
Yeah, as the day progressed the whole thing made no sense to me either, I think the excitement of a probable fault found overtook common sense, I think I need a professional in here as Im clearly missing something, thanks for all the help
dave

GreenV8S

30,482 posts

291 months

Tuesday 8th December 2020
quotequote all
Do the symptoms still suggest no fuel flow into the cylinders?

The ingredients for fuel flow are fuel pressure, 12V ish across the injector, the injector physically opening and not being blocked internally.

Can you run the pump briefly and see pressure build in the fuel rail and then hold when the pump stops?

When you briefly connect 12V across the injector can you hear it click open and closed? If you do that with pressure in the rail and the pump not running, do you see the pressure drop? If so, that's pretty strong evidence that you have fuel flow.

lancepar

1,042 posts

179 months

Tuesday 8th December 2020
quotequote all
abercoms said:
Yeah, as the day progressed the whole thing made no sense to me either, I think the excitement of a probable fault found overtook common sense, I think I need a professional in here as Im clearly missing something, thanks for all the help
dave
idea
The North of Scotland is a big place, why not put the region in your profile, you might have a TVR owner around the corner gagging to have a mess to help out.

Current restrictions allowing of course.


cool

abercoms

Original Poster:

50 posts

237 months

Tuesday 8th December 2020
quotequote all
OK heres what happens with fuel pressure, switch ignition to on, guage goes up to 2 bar then if you leave it sinks to 0, attempt to start car and as its churning over the pressure goes up to 3 bar and sits there till you give up churning, guage then drops to 0

There is 12V at all the injectors I can reach according to my meter, if I put a straight 12 source on same injectors I can hear a faint click

Ive had a NOID device and the light flashes as you churn over, again on the ones I can reach

Im in Morayshire, Ive managed to add myself to list, nearest I can see is smadmax in aberdeenshire, Ill put a post on FB

ta dave

GreenV8S

30,482 posts

291 months

Tuesday 8th December 2020
quotequote all
abercoms said:
if I put a straight 12 source on same injectors I can hear a faint click
Do you mean grounding one terminal and putting 12V on the other? That should operate the injector and cause the click you hear. If there's pressure in the fuel rail, it'll inject fuel while it's open. The fuel would normally puddle on the back of the intake valve and fall into the cylinder when the valve opens.

Are you getting fuel into the cylinders after cranking the engine over?

abercoms

Original Poster:

50 posts

237 months

Tuesday 8th December 2020
quotequote all
Yes when I put power straight from battery +on 1 side, - on other I get the faint clicks, The plugs appear dry, I just cant get the correlation between all this that appears to work but it wont fire

mentall

469 posts

137 months

Tuesday 8th December 2020
quotequote all
I go back to the first post in your previous thread, where you said the car hadn't been started for ten years.

Is it possible you've pumped the st from the bottom of the tank into the fuel rail, and blocked the feed to the injectors (which have their own tiny filters)?

This would explain your problem: adequate fuel pressure and flow, clicking injectors but dry plugs.

I can't suggest any other way to find out, or to fix the problem, but to remove, examine and clean the fuel rail and injectors. An injector cleaning and calibrating service (look on-line) will check, clean and flow-test the injectors, and give you a report, if you send them in by mail. This was another step I took, and it may have been that that solved my problem, though the report said the injectors were good.

But my car had only been off the road for two years.

If that turns out to be the problem (or even if not!), I'd also remove and clean the pump and filter, drain and flush the tank and fuel lines. Have they already been replaced with ethyl-resistant rubber? See other posts on the importance of this.

Sounds like a lot of work, but it's worth it. And you can't run a thirty-year-old car, or leave a car unused for ten years, without this sort of thing cropping up.

Good luck!

GreenV8S

30,482 posts

291 months

Tuesday 8th December 2020
quotequote all
I don't remember whether you have tried cold start spray previously.

If not, give it a squirt of that while cranking and see whether you get any signs of life. If so this would confirm that it's a fuel problem, despite all the evidence suggesting otherwise.

Also, can you confirm that while cranking it is pulling air in the intake and blowing it out the exhaust? This would rule out a broken cam chain and so on.

Penelope Stopit

11,209 posts

116 months

Wednesday 9th December 2020
quotequote all
abercoms said:
tonight I sprayed Engine start and the engine fired and ran as best it can on engine start
Ok then

Follow the following advice as it's solid, contains much logic and makes perfect sense

The plugs keep showing as dry

What else could it possibly be?

mentall said:
I go back to the first post in your previous thread, where you said the car hadn't been started for ten years.

Is it possible you've pumped the st from the bottom of the tank into the fuel rail, and blocked the feed to the injectors (which have their own tiny filters)?

This would explain your problem: adequate fuel pressure and flow, clicking injectors but dry plugs.

I can't suggest any other way to find out, or to fix the problem, but to remove, examine and clean the fuel rail and injectors. An injector cleaning and calibrating service (look on-line) will check, clean and flow-test the injectors, and give you a report, if you send them in by mail. This was another step I took, and it may have been that that solved my problem, though the report said the injectors were good.

But my car had only been off the road for two years.

If that turns out to be the problem (or even if not!), I'd also remove and clean the pump and filter, drain and flush the tank and fuel lines. Have they already been replaced with ethyl-resistant rubber? See other posts on the importance of this.

Sounds like a lot of work, but it's worth it. And you can't run a thirty-year-old car, or leave a car unused for ten years, without this sort of thing cropping up.

Good luck!

abercoms

Original Poster:

50 posts

237 months

Friday 11th December 2020
quotequote all
Evening experts smile So after what seemed like a heck of a fight Ive got the fuel rail off and the injectors out, 1st thing 5 look the same, 6th looks different, they look grubby but I dont know what Im looking at. Ive tried putting 12V across them, again I get faint click but I see no movement in the centre of the injector, is the movement small or are they crudded up inside and not moving? The fuel rail looks clean as was the fuel that dribbled out.
Whos best for rebuild? MrInjector?
ta dave