Having the throttle body only secured on the top 2 studs would potentially mean that the engine is getting too much un-metred air. It wouldn't stop the car from starting but it aint helping things.BROOMY wrote:Also a stud and 2 nuts are missing from the lower throttle body mountings.
Would this be the vaccum for fuel regulator not working from not getting enough air sucked through it.
I say this as its right next to it. Or is this not helpful?
Doesn't wanna start
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- Brianmoooore
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An engine will produce more power at most throttle openings with that particular pipe disconnected.
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It means exactly what is says. An engine will produce marginally more power at all throttle openings, with this pipe disconnected, except at WOT.
This is because the pipe reduces fuel pressure at part throttle openings, making the fuel mixture more lean - heading towards the fuel ratio for maximum economy, rather than maximum power. You don't need maximum power at part throttle openings of course, because you can compensate by opening the throttle slightly more.
What it does mean, in relation to your problem, is that lack of vacuum to the FPR isn't affecting your problem in any meaningful way.
This is because the pipe reduces fuel pressure at part throttle openings, making the fuel mixture more lean - heading towards the fuel ratio for maximum economy, rather than maximum power. You don't need maximum power at part throttle openings of course, because you can compensate by opening the throttle slightly more.
What it does mean, in relation to your problem, is that lack of vacuum to the FPR isn't affecting your problem in any meaningful way.
Went out today got the new stud n nuts fitted still wouldn't start.
So I measured the voltage at injectors was 11.8v after bout half hour of turning it over.
What should I try now?
Had fresh fuel recharged the battery about 10 million times
Looks all fine could it be a dead sensor?
What tells the fuel injectors when to squirt?
So I measured the voltage at injectors was 11.8v after bout half hour of turning it over.
What should I try now?
Had fresh fuel recharged the battery about 10 million times
Looks all fine could it be a dead sensor?
What tells the fuel injectors when to squirt?
- Brianmoooore
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Air leaking into the inlet plenum through the pipe where the hose should be connected will have far more effect on the engine than the lack of vacuum at the FPR, but neither will have anywhere near enough effect to stop an engine from starting. Refitting the hose had nothing to do with the engine starting after it was fitted.BROOMY wrote:Last time it wouldn't start after we built it, was because the FPR hose wasn't on.
When I refitted the hose it fired straight away.
Injectors are fired by the ECU earthing one of the wires connected to it. The pulse will be so short at cranking/tick over that you won't detect it with a meter. You'll need to connect up LEDs to see them.
The pulse for the injectors is initiated from the crank position sensor, but undergoes considerable processing and looking up of software tables, before it reaches the injectors.
An injector isn't going to inject fuel if there's no fuel under pressure in the fuel rail, and I'm not sure if we've even established the fuel pump works yet, or checked the rail pressure.
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CPS is responsible for sparks at the plugs as well. If the plugs are sparking, then the CPS is likely to be OK, at least when it's cold.
Ok. I'll give it a clean anyway.
It's at the front so is oil involved or can I remove it and clean it just to be safe?
It sparks but I feel they're quite weak, sparks but not a nice bright spark, a sorts of a spark but quite dull
What should I check when I go back out there?
Bear in mind it's on my drive and I can't just take things apart n leave them out.
It's at the front so is oil involved or can I remove it and clean it just to be safe?
It sparks but I feel they're quite weak, sparks but not a nice bright spark, a sorts of a spark but quite dull
What should I check when I go back out there?
Bear in mind it's on my drive and I can't just take things apart n leave them out.
- Brianmoooore
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Fuel pressure should be whatever is written on the fuel pressure regulator, if the little sensor tube is disconnected. With it connected, the pressure will be a little less with the engine running, depending on engine load.
https://www.ebay.co.uk/itm/252048726198
How does that connect to the fuel pressure regulator?
I thought you just plugged the fuel hose into it then got someone to turn the car over while you read it?
How does that connect to the fuel pressure regulator?
I thought you just plugged the fuel hose into it then got someone to turn the car over while you read it?
- Brianmoooore
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You use the tee piece and a short piece of hose to connect it into the fuel supply hose. Can be done anywhere between the pump and the fuel rail, but normally you'd disconnect the supply hose from the rail, and connect it in there.
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You'll lose any residual pressure remaining in the system when connecting it up, so the engine has to crank (or jump the fuel pump) before the gauge will read anything.
That pressure should be what's written on the FPR at this time, but will drop considerably when the engine fires and runs without any load. Full throttle will bring the pressure up again, but of course, unless you are driving the car or are on a rolling road, you can only 'blip' the throttle, or the engine will hit the limiter.
After switching the engine off, most of the pressure should be retained for several days, and if it's not, clamping off hoses will give an indication of whether the fuel pump non return valve, the FPR, a simple leaking fuel hose, or a weeping injector or two is the culprit.
That pressure should be what's written on the FPR at this time, but will drop considerably when the engine fires and runs without any load. Full throttle will bring the pressure up again, but of course, unless you are driving the car or are on a rolling road, you can only 'blip' the throttle, or the engine will hit the limiter.
After switching the engine off, most of the pressure should be retained for several days, and if it's not, clamping off hoses will give an indication of whether the fuel pump non return valve, the FPR, a simple leaking fuel hose, or a weeping injector or two is the culprit.
Now Ino something is draining my battery or the battery is poo.
Would it be a case of taking every fuse out and trying it or there another way of just testing if the battery's dead?
Old batteries used to last when stationary unused in a council garage connected up for around 5-6 month, one iv got now not new but still a good battery lasts about 2-3 week when connected up.
Any help?
Would it be a case of taking every fuse out and trying it or there another way of just testing if the battery's dead?
Old batteries used to last when stationary unused in a council garage connected up for around 5-6 month, one iv got now not new but still a good battery lasts about 2-3 week when connected up.
Any help?

