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28hodge

1.6 injector no voltage

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28hodge

Spent the day today searching and trying everything that showed up in the search to cure the issue but still no joy.

 

Car has been laid up for approx 20years, i have no idea last time it started but judging by the state of the fuel pump and the varnish on it ill assume its not started in 20 years. so heres where we are.

 

New bosch fuel pump

Fuel pump primes and rail has fuel

New fuel filter

Fresh fuel

Fuel pump primes and then shuts down so to me that means the tach relay is working correctly

Removed fuel hose and ran some fuel through to get rid of stale fuel and any muck etc

Plugs removed and sparking when cranking, decent blue spart so to me this also confirms the amplifier and dist sensor wire are working

Plugs are dry as a bone, engine will crank but injectors clearly are not firing

Have no voltage at the injectors when ign ON, have 6v when cranking testing with multi but from what i've read not sue if thats not just utilising my meter to complete the circuit.

 

I don't want to remove the fuel rail and injectors without first removing the inlet as have read the caps can come off and drop into the head if you are unlucky with the valve position, given how long the car has sat etc id be wary of the injectors being stuck. also i dont think its going to prove much more than i already know, which is that the injectors are not firing.

 

I am thinking from reading that i need to do the following - 

 

Trace the sensor wire back to the ECU and test continuity through it, anybody advise which pin in the ecu plug i need to test on?

the ECU triggers the earth, i keep reading about the ecu earth and checking that? where is this?

am i right to assume that if the fuel pump runs and im getting spark that both the tach relay and the ign amplifier and dist sense wire are all good?

Bridge the thick brown wire into the tach relay across the fuel pump and injector trigger wire

spray easy strat into the inlet and see if it will fire and prove it is just lacking fuel.

 

Anything else anyone can help with.

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welshpug

that should help with the wiring somewhat, as would a Haynes workshop manual.

 

sounds like the ignition system is good, injectors should have powrr if everything else is powering up as you say, might still be the relay, earth is on the gearbox.

 

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28hodge

Thanks Welshpug, I have haynes but I struggle with correlating a wiring schematic to the mess of wiring you then find in the car. I have a clicking starter motor also so need to sort that and find the resistance in that, but i would rather get it running before I start chopping.

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Tom Fenton

Unless you are checking the injector pulses with an oscilloscope then you won’t see anything meaningful, a multimeter can’t react quickly enough.

I’d be reasonably sure that the electrical side is probably ok, and your problem is the injectors themselves stuck shut from years of being sat. 

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Tom Fenton

Test the injectors by rigging power and earth. If they are working you should hear them click when you apply power. AsI say I would be reasonably sure after that amount of time they are stuck. 

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28hodge
25 minutes ago, Tom Fenton said:

Test the injectors by rigging power and earth. If they are working you should hear them click when you apply power. AsI say I would be reasonably sure after that amount of time they are stuck. 

Tom can I do this by rigging up two leads from a separate battery or do I need to bridge across the tach relay? 

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28hodge

I also thought I should be able to see 12v at the connector with the ign in the on position, which I can’t. If that’s not right then I’m inclined to agree that they will be stuck. Only reason I hadn’t pulled them out to put in the ultrasonic cleaner is because I wasn’t getting 12v with ign on which I thought I should

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pugdamo

I could be wrong but I thought with the ignition on there should be a constant 12v on 1 pin to each of the injectors. I didn't think that 12v was only there under cranking. 

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PhilNW
2 hours ago, Tom Fenton said:

Unless you are checking the injector pulses with an oscilloscope then you won’t see anything meaningful, a multimeter can’t react quickly enough

 With a reasonable digital multimeter I have actually seen it work, wait for a steady voltage on the meter and then crank the engine,(might be a 2 handed operation) you may see a change in the reading from the steady value which I took to mean that the injectors were pulsing, maybe worth a try.

 

As others have said probably gummed up injectors.

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28hodge
4 minutes ago, PhilNW said:

 With a reasonable digital multimeter I have actually seen it work, wait for a steady voltage on the meter and then crank the engine,(might be a 2 handed operation) you may see a change in the reading from the steady value which I took to mean that the injectors were pulsing, maybe worth a try.

 

As others have said probably gummed up injectors.

Yeah that’s the thing, I only see any voltage if it’s cranking, with the ignition in the on position I get no reading on the multimeter on either pin.

 

also been out and attached a spare battery across the injector pins and get nothing, no click at all, so injectors are gummed up which isn’t a surprise but I also don’t think they are getting any power.

Edited by 28hodge

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PhilNW

Sorry, was not quite clear injectors get their power via the tachy relay, so will only see a voltage while cranking. Is there any variations in the voltage reading while cranking?  I used this technique to find a dodgy earth on one of the injectors. 

 

As you have attached a battery across the injector terminals and got nothing, looks like you have the answer.

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28hodge

Ok, so just to confirm, if I can’t see 12v at the injectors with the ignition in the on position that is normal and not an issue.

 

I can see a voltage across the injector when cranking but that’s on a multimeter so may be meaningless so will see if a mate has an oscilloscope. I did wire a light across it last night and that didn’t light when cranking but it was with a indicator repeater side light so will do it again with a clear bulb this morn at some point.

 

I’ll grab some easy start as well and see if it’ll fire off that, as then I know everything else is ok and I just need to get the injectors to fire. If that works then I’ll pull the inlet off and remove the injectors etc. Need to go and locate my ultrasonic cleaner!

Edited by 28hodge

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28hodge

Is easy start subject to some weird EU import ban? 3 different garages with decent shops on them and decent automotive sections in those shops, zero easy start, Motor factors is about a 25 min drive away, was tempted to drop some fuel or brake cleaner into the inlet but im pretty happy that given no clicking on the injectors that they need to come out to be cleaned regardless (that and the potential period of time they have sat for) plus the rest of the ignition circuit is working.

 

So i looked at it and thought id risk it to just pull the injectors out with the inlet attached. and low and behold 2 caps popped off the injectors in the process, and the valve was fully open on one, great!!.

 

However i duct taped a empty biro onto the end of my henry hoover, then duct taped a tube onto the end of that and pulled the spark plug out and had the cap retrieved in 30secs, the other was still in the inlet track so got that one out with the hoover down the injector hole.

 

My brother has a ultrasonic cleaner, i cant put my hands on mine and i think i may have lent it to someone for it to never return! so i will rig up some wiring so i can fire the injectors whilst they are in the ultrasonic cleaner. See how they turn up but they may be pretty goosed and cause poor running indefinitely so i may look at getting a fresh set. 

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welshpug

I thought essy start was a bradex product, British made.

 

 

its start ya bastard that I dont think is available any more, which is a Nulon aussie brand

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DamirGTI

Possibly "easy start" doesn't sell much these days ?! , low demand for having it on sale/stock in ordinary local "car grocery" shops .. Or the ebay , amazon an the likes killed the direct supply on the spot when you need it .

Interesting , over here it can be found pretty much on almost all petrol stations .. also , local small shops still have all kinds of spray stuff on sale .

 

In absence of "easy start" spray (which is mostly ether) , instead , can use carb cleaner or brake cleaner spray (MAF cleaner too .. though that one is bit expensive) they're all pretty much the same stuff inside the can  ... mixtures of alcohols , ketones (acetone) and aliphatic/aromatic hydrocarbons .. cheaper ones are by higher % alcohols and acetone , little bit more pricey (better/stronger) will contain more hydrocarbons less alcohols .

 

D

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PhilNW

easy start available at Toolstation Kendal, not sure how close that is to you.

 

Now a Holts product apparently

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Richard309Sri XU5JA 205GTi

I got two cans recently when I was getting my engine started up again. One from amazon delivered to the door;- Mannol 9669 - (Motor Starter start pilot spray,450 ml),It worked ok.

 

 

Edited by Richard309Sri XU5JA 205GTi

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28hodge
3 hours ago, PhilNW said:

easy start available at Toolstation Kendal, not sure how close that is to you.

 

Now a Holts product apparently

Yeah about 25mins away. 

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