Cranking But Not Starting

[PUGPIRATE 0]

I'm having a major headache getting my 205 gentry to start (XU9J1 DFZ). I've shorted something electrical out or inadvertently pulled something out in the engine bay. I was basically fitting a new (thicker) cable to my starter motor to avoid the 'sticky starter issue that an overly hot engine sometimes causes when this happened and I either pulled something too hard or sorted something out in the process!

 

Now, when I turn the ignition key I can't get the car to start. The starter is just fine. I tried another one just to make sure. There is spark (I tested this using a timing light). However, there doesn't seem to be any fuel pressure. I don't think it's the fuel pump relay as I tried it with a spare. I've disconnected the fuel hose in the engine and pressure is almost non-existent.

 

I've also tried bypassing the fuel pump rely by connecting it to 12V. I can hear it running when I do this but it does nothing to help with my starting issue as the car still won't start! So the fuel pump works as does (I believe) the fuel relay but the fuel system isn't being 'activated' when I turn on the ignition.

 

Any ideas, guys?

[smithy 1]

only thing i can think is you may have pulled one of the plugs out of the shunt box by radiator,i did this a while back and could not get it to start although cannot remember if it was fuel,spark or both at fault with it pulled out?

 

am i right to assume the engine actually cranks over as you say it sparks?

 

what injection system does the dfz have is it jetronic or motronic with a crank sensor?

 

edit just seen in title it cranks but not start

Edited August 14, 2011 by smithy

[PUGPIRATE 0]

only thing i can think is you may have pulled one of the plugs out of the shunt box by radiator,i did this a while back and could not get it to start although cannot remember if it was fuel,spark or both at fault with it pulled out?

 

am i right to assume the engine actually cranks over as you say it sparks?

 

what injection system does the dfz have is it jetronic or motronic with a crank sensor?

 

edit just seen in title it cranks but not start

[PUGPIRATE 0]

LU2-Jetronic.

 

I guess it depends on what you mean by crank. I mean, the starter motor is turning and a regular spark is being produced at the first spark plug while I turn the starter motor. Other than that there's no life there. It simply doesn't start.

 

I don't know what you mean by 'plugs in the shunt box' so can't comment on that. Thanks for the reply though!

Edited August 14, 2011 by PUGPIRATE

[PUGPIRATE 0]

Worked out what you meant by 'shuntbox' - everything in there looks fine. Am starting to pull my hair out.

 

 

LU2-Jetronic.

 

I guess it depends on what you mean by crank. I mean, the starter motor is turning and a regular spark is being produced at the first spark plug while I turn the starter motor. Other than that there's no life there. It simply doesn't start.

 

I don't know what you mean by 'plugs in the shunt box' so can't comment on that. Thanks for the reply though!

[PUGPIRATE 0]

Could these symptoms suggest a faulty ECU do you think? The fuel pump seems to be be fine (as is the relay) but neither are receiving voltage.

[smithy 1]

the tachy relay up by ecu controls fuel pump and injectors,it is energised by the starter solenoid trigger wire on cranking to provide fuelling and also once running it is done from the ignition system via the sensor inside the dizzy.

 

what you need to check is all the basics first like plugs all connected on dizzy,coil,amp and AFM,also worth checking the earths on gearbox.

[PUGPIRATE 0]

the tachy relay up by ecu controls fuel pump and injectors,it is energised by the starter solenoid trigger wire on cranking to provide fuelling and also once running it is done from the ignition system via the sensor inside the dizzy.

 

what you need to check is all the basics first like plugs all connected on dizzy,coil,amp and AFM,also worth checking the earths on gearbox.

 

 

"the tachy relay up by ecu controls fuel pump and injectors,it is energised by the starter solenoid trigger wire on cranking to provide fuelling"

 

 

Neither the fuel pump nor the the injectors are receiving any voltage on cranking - I checked this using a voltmeter. There's no pressure at the fuel rail and no priming at the fuel pump with the key in any position. And even when they do receive a 12V supply (when I bypass the tachymetric relay by supplying a 12V charge direct to the fuel pump and injectors when cranking) the engine still won't run. All the connections that I can see are secure - I spent most of the past two days checking this.

Edited August 15, 2011 by PUGPIRATE

[smithy 1]

Have you got good earth to injectors?

If you put direct feed to them and still don't work it suggests to me they are not earthed.

Earthing is done via ECU they have perm feed during normal operation the ECU provides earth to fire them.

 

Did you check the earth point on gearbox?

Also do you have a Haynes/circuit drawing so you can trace back and test wiring to ecu?

[smithy 1]

Also where did you run the thicker wire from and was fitting this wire the start of your problems?

[PUGPIRATE 0]

Have you got good earth to injectors?

If you put direct feed to them and still don't work it suggests to me they are not earthed.

Earthing is done via ECU they have perm feed during normal operation the ECU provides earth to fire them.

 

Did you check the earth point on gearbox?

Also do you have a Haynes/circuit drawing so you can trace back and test wiring to ecu?

Thanks for the reply. No, if I bypass the tachy relay and provide a direct feed both the fuel pump and injectors DO work - but the engine still doesn't run.

 

I actually fitted the thicker wire a couple of years ago and connected it to the thick orange wire that comes from the ECU. It's worked absolutely fine since then. However, I did have the 'sticky starter' syndrome for the first time in years a few weeks back and decided to overhaul that wire with an even thicker one re-routed away from any hotspots. Unfortunately I managed to briefly earth the wire or briefly connect it to a live one and inadvertently did something to damage something in the process.

 

I'm pretty sure that I've shorted something out or pulled something loose. As I ran that 'thicker' starter wire to the orange wire coming from the ECU and that this wire was at 'ground zero' I'm thinking that the ECU is somehow involved hence the question.

 

The earths by the gearbox seem fine. They're solidly connected with no corrosion. Will be looking at the ECU today but I'm not entirely sure what I can do with it.

 

Yes, I have the circuit diagram.

[smithy 1]

not a lot you can see on the ecu best off getting a replacement to try in my opinion.

 

the starter wire should not be live unless key in the start position so i doubt it has shorted out unless you have somehow nicked a couple of wires at ECU plug while connecting your thicker one up?

are the 2 brown plugs down by heater matrix all ok?

[PUGPIRATE 0]

Thanks for the reply. No, if I bypass the tachy relay and provide a direct feed both the fuel pump and injectors DO work - but the engine still doesn't run.

 

I actually fitted the thicker wire a couple of years ago and connected it to the thick orange wire that comes from the ECU. It's worked absolutely fine since then. However, I did have the 'sticky starter' syndrome for the first time in years a few weeks back and decided to overhaul that wire with an even thicker one re-routed away from any hotspots. Unfortunately I managed to briefly earth the wire or briefly connect it to a live one and inadvertently did something to damage something in the process.

 

I'm pretty sure that I've shorted something out or pulled something loose. As I ran that 'thicker' starter wire to the orange wire coming from the ECU and that this wire was at 'ground zero' I'm thinking that the ECU is somehow involved hence the question.

 

The earths by the gearbox seem fine. They're solidly connected with no corrosion. Will be looking at the ECU today but I'm not entirely sure what I can do with it.

 

Yes, I have the circuit diagram.

[PUGPIRATE 0]

not a lot you can see on the ecu best off getting a replacement to try in my opinion.

 

the starter wire should not be live unless key in the start position so i doubt it has shorted out unless you have somehow nicked a couple of wires at ECU plug while connecting your thicker one up?

are the 2 brown plugs down by heater matrix all ok?

 

Having taken off the paneling I can now see that the thicker wire was connected to the orange wire coming from the ignition (rather than the ECU) - I did it a couple of years back.

 

What would be the likely culprit for the symptoms I've described if I accidentally connected that ignition wire to a live 12V(as I briefly did and which made the starter briefly come to life at the time?) before I noticed the problem with starting? Could that have damaged something related to fueling?

Edited August 16, 2011 by PUGPIRATE

[smithy 1]

blown fuse or spiked ECU?

[PUGPIRATE 0]

blown fuse or spiked ECU?

 

Cheers, Smithy. Fuses in fuse box were first thing I checked. They're all fine. Same goes for ones in engine bay in the box by radiator and power steering fluid reservoir. That's all of them isn't it?

 

Am thinking about getting a dirt cheap ECU from eBay just to see how this affects things and then pay a bit more for the correct model number ECU once I've established that it's actually the ECU that's at fault. Are they all interchangable for such a purpose (I understand that rough running might be an issue)?

 

Will any old Jetronic ECU work? Any advice will be appreciated!

[welshpug 1,666]

check the wire from the distributor to the coil and back to the ecu, if this is damaged you wont get an injection pulse or a trigger to the fuel pump relay, sounds like its getting to the coil/ign amp fine if there is spark though.

[smithy 1]

Cheers, Smithy. Fuses in fuse box were first thing I checked. They're all fine. Same goes for ones in engine bay in the box by radiator and power steering fluid reservoir. That's all of them isn't it?

 

Am thinking about getting a dirt cheap ECU from eBay just to see how this affects things and then pay a bit more for the correct model number ECU once I've established that it's actually the ECU that's at fault. Are they all interchangable for such a purpose (I understand that rough running might be an issue)?

 

Will any old Jetronic ECU work? Any advice will be appreciated!

 

 

i think any jetronic ECU will work well enough to prove if yours is faulty but it would be better posting a wanted ad on here and see if anyone has a known good one that is correct rather than chancing the fleabay

[PUGPIRATE 0]

check the wire from the distributor to the coil and back to the ecu, if this is damaged you wont get an injection pulse or a trigger to the fuel pump relay, sounds like its getting to the coil/ign amp fine if there is spark though.

 

Good tip. The wire from the distributor to the coil is in good nick but I'll take a gander at the one to the ECU tomorrow.

[PUGPIRATE 0]

i think any jetronic ECU will work well enough to prove if yours is faulty but it would be better posting a wanted ad on here and see if anyone has a known good one that is correct rather than chancing the fleabay

 

That sounds like good advice. Thanks for the continued input!

[PUGPIRATE 0]

check the wire from the distributor to the coil and back to the ecu, if this is damaged you wont get an injection pulse or a trigger to the fuel pump relay, sounds like its getting to the coil/ign amp fine if there is spark though.

 

Am having trouble working out which wire you mean. On the wiring diagram I can't see a wire running from the ignition coil direct to the ECU. However, there is one running from there to the tachymetric relay unless I'm very much mistaken. Is this the one that you mean?

 

Tried another ECU today and still no joy. Am grasping at straws now!

[PUGPIRATE 0]

Am having trouble working out which wire you mean. On the wiring diagram I can't see a wire running from the ignition coil direct to the ECU. However, there is one running from there to the tachymetric relay unless I'm very much mistaken. Is this the one that you mean?

 

Tried another ECU today and still no joy. Am grasping at straws now!

 

Had a look at the wires coming from the ECU this afternoon and verified that the fuel pump and injectors are working when a 12V supply is fed to them at this point. It doesn't look like it's the ECU given the failure of the substitute ECU to make any difference. So I'm thinking that the signalling to the ECU that you refer to must be the issue. However, I need a bit of help identifying that source so any tips you give me would be appreciated i.e colour and location of likely wiring, etc.

 

Thanks as always.

[PUGPIRATE 0]

It looks like I've been misrepresenting the situation.

 

I've been cranking the engine with the starter motor but having detached the starter solenoid lead it seems clear that the fuel pump and injectors ARE being activated after all. The fact that the fuel pump is no longer being 'primed' caused me to leap to a couple of conclusions.

 

However the fact remains that although the starter is cranking it, the engine it will at best seem on the verge of starting but will conk out almost immediately. All the wiring seems pretty sound as do the connections.

 

Any suggestions?

[PUGPIRATE 0]

Here are how things presently stand:

 

205 Gentry (1992 XU9J1 - 1.9i with CAT) will not start. When the engine is cranked it sounds as if it's on the verge of starting but never quite makes it.

 

Have been over the wiring repeatedly and it seems sound. Earth points are nice and clean and tight. I have checked very thoroughly for broken wires or detached connectors and this doesn't seem to be an issue.

 

Starter will crank and spark plugs are receiving a spark (tested with a timing light). Fuel pump is no longer priming as it used to but is working. I turned on ignition with starter solenoid detached and petrol was being pumped. I detached the hose from the fuel rail and put it in a petrol can and plenty of petrol flowed through.

 

I've tested the voltages on the tachmetric relay and these all seem perfectly normal. I've spent many hours (most of this week) trying to get to the bottom of this. It's very frustrating. I really don't want to scrap this car as I've invested so much time in it over the years.

 

It was working fine until the other week. However, it refused to start after a brief stop a while back so I figured I'd look at re-routing the thicker cable that I'd attached to the starter solenoid to get over the 'sticky starter' problem that used to be a major headache. I have a thick cable running from one of the orange ignition leads inside the car to the solenoid. It's been working fine for a couple of years having previously stranded me on several occasions.

 

Unfortunately, when I was trying to untangle it all I seem to have briefly connected it to a live 12V and damaged something along the way. Or yanked something out. My instincts tell me that a component has been damaged. Ignition amp maybe? Question is, which one?

 

I had thought that it was the ECU but that seems fine. As is the tachy.

Edited August 19, 2011 by PUGPIRATE

[AndyJ 1]

When cranking, can you smell petrol out of the exhaust?

You say it nearly starts, there is a spark, the fuel pump is working. If you get a stink out the exhaust the injectors are firing, so all the ingredients are there for it to work... indicating maybe it's a mixture problem? I would be looking at the connections to the AFM and engine temperature sensor, have you tested continuity from these back to the ECU plug?

 

Ignition components could also be responsible, even if you get a flash from the timing strobe the spark may be weak - have you actually checked the condition of the dizzy cap and leads closely?

 

Otherwise I would be reduced to checking every ecu pin is continuous to its respective connector a the other end, cos you seen to have covered most of it already.