Starting problems, lumpy acceleration
Discussion
Morning all.
I have an '88 S1 (so 2.8)
It is suffering with intermittent starting problems, sometimes it will fire into life immediately, other times (usually first thing in the morning) I will need to churn over for up to 30 seconds to get it to fire, and then it runs on 1, 2, 3, etc cylinders until its happy (another 30 seconds)
I have un-plugged the 7th injector to see if that makes any difference (flooding etc) but it doesnt seem to.
It's about 50/50 as to start / no start.
Where should I start?
I have replaced the plugs and coil, they looked fine, cleaned out the dizzy cap and rotor which looked new anyway...
I have an '88 S1 (so 2.8)
It is suffering with intermittent starting problems, sometimes it will fire into life immediately, other times (usually first thing in the morning) I will need to churn over for up to 30 seconds to get it to fire, and then it runs on 1, 2, 3, etc cylinders until its happy (another 30 seconds)
I have un-plugged the 7th injector to see if that makes any difference (flooding etc) but it doesnt seem to.
It's about 50/50 as to start / no start.
Where should I start?
I have replaced the plugs and coil, they looked fine, cleaned out the dizzy cap and rotor which looked new anyway...
Edited by Darkcat on Saturday 8th August 09:45
Hmmm....... 2.8 you say? That makes yours an S1.5. Poor starting could be due to any of a number of causes:
Electrical: Are all the engine electrical connections, cables and earth points clean and sound & free from corrosion? Can you hear the fuel pump "buzz" for a moment each time you turn on the ign switch?
Is the green cold start relay in good condition? It is cunningly buried amongst a mess of cables right in the rainwater drain path between the nearside inner wing and the passenger footwell bulkhead. It can fill with water and that's not good for efficient operation.
Is your fuel pump relay and its' connector base in good condition with no signs of overheating? Are the blades making good contact with the female connectors in the socket base? The base can melt and the female ends can push up and not engage properly.
Are all the relevant fuses and their bases in good condition and making proper contact?
Are your fuel pump cable connections clean, dry and tight? Also check the adjacent earth connection. Is there any contamination ( rust particles etc ) inside the fuel tank? Is there a filter before the fuel pump either external or inside the tank that is getting partially blocked? If it was, your engine would falter under load as well as being reluctant to start.
Are the connections at the back of your tacho/rev-counter secure?
Ignition:
Are you getting a healthy spark at the plugs? Is the carbon centre contact in the distributor in good condition with the spring intact? Don't try to pull the centre out, it will drop out if the spring is broken.
Were the spark plugs that you removed in a healthy state, or oily or wet with fuel? Is your ignition timing set correctly?
Is there any visible fraying of the small wires to the little module on the side of the distributor?
Does your car have the dreaded "yellow connector"? ( behind the steering column shroud ) This is prone to overheating and burning its' contacts, you need to pull it apart to check it. If you do have this, it's best to replace it with decent soldered joints and shrink sleeving.
Fuel:
Is the petrol nice and fresh or has it been sitting for a long time?
When churning the engine over, are you getting a smell of fuel? Is the engine flooding? Could be mixture setting is not set correctly.
Or perhaps fuel starvation issues? Does the engine run ok under load?
When was the main fuel filter ( in the engine bay, nearside ) last changed?
The K-Jetronic fuel system is very sensitive to fuel pressure.
Richard ( greymrj on here ) has spent a lot of time sorting out his S1's running problems, and could probably tell you more about it than I can. Once set up, it is generally a reliable system, the only user-adjustable bit is the mixture, the rest needs specialist knowledge and equipment.
Inlet manifold / vacuum hosea air leak: With the engine running, try spraying carb cleaner or Bradex Easi-start in the general area of these bits and the brake servo & hoses. If the revs increase, this means you have a leak. The hoses can become porous with age.
That's a few things to be going on with, but not a comprehensive list.
The main thing it to approach it in a logical fashion, don't just go changing things at random.
Good luck,
Glen
Edited by glenrobbo on Friday 7th August 16:25
Hi there. Impossible to diagnose at this stage, just too many options.
I do agree entirely with Glen, particularly that you should be very methodical and not try too many things at once.
At one time I would have associated a fault like that with 'tracking' of the spark somewhere so it isnt getting to all the cylinders until the revs are up a bit, or the engine warms a bit. Tracking can happen on the outside of the dissy cap just as easily as the inside, or between bunches of leads. WD40 would be the good old cure for that. Summer it may be but there has been a lot of damp to cause condensation.
The bigger 'problem' you have is the K Jetronic, a fault in there can be hard to trace. But before we get into the dark and mysterious secrets of the K jet you really need to ensure everything else is right first.
Just one point, did you also post on Facebook and show a possible faulty wire to a water housing in front of the plenum chamber? I think the wire you are referring to is the temperature sensor for the water temp gauge, the original wiring colour would have been red with a white tracer. The other sensor on that housing, with two wires, is a temperature sensor for the K jet system.
I do agree entirely with Glen, particularly that you should be very methodical and not try too many things at once.
At one time I would have associated a fault like that with 'tracking' of the spark somewhere so it isnt getting to all the cylinders until the revs are up a bit, or the engine warms a bit. Tracking can happen on the outside of the dissy cap just as easily as the inside, or between bunches of leads. WD40 would be the good old cure for that. Summer it may be but there has been a lot of damp to cause condensation.
The bigger 'problem' you have is the K Jetronic, a fault in there can be hard to trace. But before we get into the dark and mysterious secrets of the K jet you really need to ensure everything else is right first.
Just one point, did you also post on Facebook and show a possible faulty wire to a water housing in front of the plenum chamber? I think the wire you are referring to is the temperature sensor for the water temp gauge, the original wiring colour would have been red with a white tracer. The other sensor on that housing, with two wires, is a temperature sensor for the K jet system.
Thanks both, excellent info, I will start going over it today and report back any findings.
Sorry I got it slightly wrong, I meant S1, not S2!!\
Yes that was me, it seems odd that the temp gauge is working perfectly well with the connection so loose!!
Sorry I got it slightly wrong, I meant S1, not S2!!\
Yes that was me, it seems odd that the temp gauge is working perfectly well with the connection so loose!!
Edited by Darkcat on Saturday 8th August 10:06
I'm going through the wiring at the moment, it is the worst mess I've ever come across.
But yes i'll try try that...!!
Actually the reason that i started looking at the wiring this weekend was that the lights dont work (front or back, sidelight, dip, nor full beam)
The indicators work though!
I've removed a load of redundant crap from the car: an old alarm, also the immobiliser (as i want to fit a more modern combined alarm/immobiliser)
various bodges and melted crimp connectors etc.
Can't get the lights to work still. I THINK I need to be getting 12v to the switch in the dash but I don't have a wiring diagram.
But yes i'll try try that...!!
Actually the reason that i started looking at the wiring this weekend was that the lights dont work (front or back, sidelight, dip, nor full beam)
The indicators work though!
I've removed a load of redundant crap from the car: an old alarm, also the immobiliser (as i want to fit a more modern combined alarm/immobiliser)
various bodges and melted crimp connectors etc.
Can't get the lights to work still. I THINK I need to be getting 12v to the switch in the dash but I don't have a wiring diagram.
I've just checked it and Philpott has sent you the right one. You will see that it identifies several components which are part of the K Jetronic system which is only on the S1. There is a separate, and substantially different, one for the 2.9 EFi engine.
Having said that: you can use that diagram to show you which wires SHOULD be doing what. There are other wires in the harness which simply are not on the diagram! You have to learn to try to find the right wires by colour codes and not to be fooled by 'red herrings' that TVR put in to entertain us!
The S1 was very much a car under development using some bits/ideas from the 2.8 wedges. My understanding is that TVR knew they were going to get the 2.9EFi, which Ford were already using, but the S had to be out before the 2.9 was available to a small customer firm like TVR.
Having said that: you can use that diagram to show you which wires SHOULD be doing what. There are other wires in the harness which simply are not on the diagram! You have to learn to try to find the right wires by colour codes and not to be fooled by 'red herrings' that TVR put in to entertain us!
The S1 was very much a car under development using some bits/ideas from the 2.8 wedges. My understanding is that TVR knew they were going to get the 2.9EFi, which Ford were already using, but the S had to be out before the 2.9 was available to a small customer firm like TVR.
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