My S2's seriously missing its beat
Discussion
Any advice please. My S2 went through a puddle the size of a small lake a couple of weeks ago and I now have engine troubles...dont know if definately connected or not.
Firstly the Fuel pump died 20 minutes after the soaking but I changed that ok after the AA got me home.The engine was still running fine up to then.
(Then the brakes sprung a fluid leak from the rear drums so they have been sorted, more expense!)
Since the testing of the engine after fitting the new fuel pump it has developed a worsening lumpiness and missing so that it is now nearly undriveable. It is fine on tickover and reving when stationery but drive it and all of a sudden it pinks, the revs drop, it sometimes backfires, wants to die and feels like only three cylinders of six are actually working. It is intermitant and runs ok for a minute they starts to pink and shudder violently. Depress the clutch and the revs drop and you can build them again slowly until it happens again a moment later. It does not generally stall but if it does it restarts directly.
Changing the Throttle Pot for a spare has improved it but not cured it. The Air Flow Meters have been cleaned, Air bypass valve the same, Distributor and leads checked, coil is new and connections good, ignition enhancer on distributor clean & looks ok and all connections checked, cleaned and given a WD 40 spray. Disconnecting engine temp sender makes no difference and disconnection of other sensors when idleing changes revs as expected but engine ticks over fine and returns to normal when sensor reconnected again.
Any ideas or guidance PLEASE?
Firstly the Fuel pump died 20 minutes after the soaking but I changed that ok after the AA got me home.The engine was still running fine up to then.
(Then the brakes sprung a fluid leak from the rear drums so they have been sorted, more expense!)
Since the testing of the engine after fitting the new fuel pump it has developed a worsening lumpiness and missing so that it is now nearly undriveable. It is fine on tickover and reving when stationery but drive it and all of a sudden it pinks, the revs drop, it sometimes backfires, wants to die and feels like only three cylinders of six are actually working. It is intermitant and runs ok for a minute they starts to pink and shudder violently. Depress the clutch and the revs drop and you can build them again slowly until it happens again a moment later. It does not generally stall but if it does it restarts directly.
Changing the Throttle Pot for a spare has improved it but not cured it. The Air Flow Meters have been cleaned, Air bypass valve the same, Distributor and leads checked, coil is new and connections good, ignition enhancer on distributor clean & looks ok and all connections checked, cleaned and given a WD 40 spray. Disconnecting engine temp sender makes no difference and disconnection of other sensors when idleing changes revs as expected but engine ticks over fine and returns to normal when sensor reconnected again.
Any ideas or guidance PLEASE?
This may sound crazy but try pulling the exhaust off from the downpipes and take it for a run (it's gonna be loud lol). I had very similar symptoms a couple of years ago. It would run and rev fine whilst stationary but try to drive and would not rev over about 2000/2500 and would choke. Exhaust was blocked. If this puddle was deep enough to get into yer pipes it could well be restricting badly which would give these kind of problems.
Carl.
Carl.
Thanks guys.
Will check out 'Scorpio engine problems' site in more detail but think my engines faultering is more extream than those covered I have seen diagnosed.
Exhaust...engine was running fine after puddle and dont think this is at fault as engine ran fine for twenty minuses afterwards and will sit at 5000 revs OK when standing.
Fuel starvation was my first thought but I am happy I fitted the pump correctly and it will hold revs when stationery and a major part of the time when driving. Fuel filter was changed last year with several pipes and I assume any airlocks caused when I clamped the feed pipe would have long since cleared. Wiring loom and injectors are newer replacements than originals and are in good condition in a rubber tube over engine to protect then from worst of heat. I have an FSE boost valve thingy in place of fuel regulator but think this should be ok and uneffected. Vaccumn hose is fine but I could have got a little water into the tank past the filler cap seal as I later found the drain pipe was blocked. It would have been a very very small amount though and I don't think it could be responsible.
Any observations or ideas guys?
Thanks,
Tim
Will check out 'Scorpio engine problems' site in more detail but think my engines faultering is more extream than those covered I have seen diagnosed.
Exhaust...engine was running fine after puddle and dont think this is at fault as engine ran fine for twenty minuses afterwards and will sit at 5000 revs OK when standing.
Fuel starvation was my first thought but I am happy I fitted the pump correctly and it will hold revs when stationery and a major part of the time when driving. Fuel filter was changed last year with several pipes and I assume any airlocks caused when I clamped the feed pipe would have long since cleared. Wiring loom and injectors are newer replacements than originals and are in good condition in a rubber tube over engine to protect then from worst of heat. I have an FSE boost valve thingy in place of fuel regulator but think this should be ok and uneffected. Vaccumn hose is fine but I could have got a little water into the tank past the filler cap seal as I later found the drain pipe was blocked. It would have been a very very small amount though and I don't think it could be responsible.
Any observations or ideas guys?
Thanks,
Tim
Just to clarify. If you start the engine from fully cold, is it ok for a short while and then starts to act up? If so once it starts to act up will it then not rev freely after that even after a restart? If you leave the engine to go fully cold again does the cycle begin again in the same way?
if its not fuel its got to be electrics.
go round all the connectors and clean and wd40 and put back together.
Check dizzy cap for water, not sure if the s2 has the same connector from teh dizzy to the ecu. This is very low voltage pulsed signal from the hall sensor in the dizzy, very sensitive to a bad connection.
Good luck fella keep us posted.
m
go round all the connectors and clean and wd40 and put back together.
Check dizzy cap for water, not sure if the s2 has the same connector from teh dizzy to the ecu. This is very low voltage pulsed signal from the hall sensor in the dizzy, very sensitive to a bad connection.
Good luck fella keep us posted.
m
I will have a look at plugs as you suggest but don't think the engine would have taken in to much without knowing all about it directly afterwards...seriously bent conrods a probability!
The air filter got pretty wet but the air flow meters were not too bad and I can't see liquid water getting up the long inlet tubes and into the plenium...it's all uphill. Only a mist of damp air would have been sucked in through the filter for a spell but the engine ran fine for a time afterwards. The oil is not contaminated and no slime at the filler cap or white exhaust indications. Also the problem is getting worse though everything has had two weeks to dry out by now even if I have missed drying it afterwards.
It is curious that changing the TP has improved things a bit...perhaps indicating a remaining electrical rather than fuel problem???
The air filter got pretty wet but the air flow meters were not too bad and I can't see liquid water getting up the long inlet tubes and into the plenium...it's all uphill. Only a mist of damp air would have been sucked in through the filter for a spell but the engine ran fine for a time afterwards. The oil is not contaminated and no slime at the filler cap or white exhaust indications. Also the problem is getting worse though everything has had two weeks to dry out by now even if I have missed drying it afterwards.
It is curious that changing the TP has improved things a bit...perhaps indicating a remaining electrical rather than fuel problem???
Sorry Carl. The engine starts as normal when cold. If I take it out straight away the problem is worse because I have the added tendancy of a cold engine to be a bit resistant to pick up.
Only after driving a few hundred yards, even on a warm engine, the pinking and shuddering starts and the engine pulls erratically. If I depress the clutch, the engine revs fine but when clutch is released it will return again after a few moments under load. Severe power loss, immediate drop in revs, backfire or popping, shuddering and wants to die unless I depress cluth again. Might then be fine for perhaps a minute before does same again.
Only after driving a few hundred yards, even on a warm engine, the pinking and shuddering starts and the engine pulls erratically. If I depress the clutch, the engine revs fine but when clutch is released it will return again after a few moments under load. Severe power loss, immediate drop in revs, backfire or popping, shuddering and wants to die unless I depress cluth again. Might then be fine for perhaps a minute before does same again.
Tim..
What made the original pump die? Did water get into it or did the water knack the electrics? It may be possible that whatever caused the first pump to fail is giving the new pump problems.
I have also had problems with the fuel pump relay. Check that all connections especially the small resistor at the top:
Best of luck
(another) Tim
F908tim said:
....Only after driving a few hundred yards, even on a warm engine, the pinking and shuddering starts and the engine pulls erratically. If I depress the clutch, the engine revs fine but when clutch is released it will return again after a few moments under load. Severe power loss, immediate drop in revs, backfire or popping, shuddering and wants to die unless I depress cluth again. Might then be fine for perhaps a minute before does same again.
Those were the symptoms I had when rust in the tank was blocking the pump inlet, ie. fuel starvation.What made the original pump die? Did water get into it or did the water knack the electrics? It may be possible that whatever caused the first pump to fail is giving the new pump problems.
I have also had problems with the fuel pump relay. Check that all connections especially the small resistor at the top:
Best of luck
(another) Tim
F908tim said:
.....Wiring loom and injectors are newer replacements than originals and are in good condition in a rubber tube over engine to protect then from worst of heat..... Tim
TimCould it be that water got into your rubber tube and is now causing intermittent connections in the multiway connector that sits under the coil and hence funny sensor readings are sent back to the ECU which then does stupid things to try and compensate?
Good luck
Mick
Thanks guys. Still no nearer fixing it though.
Don't know why pump stopped working. The AA guy agreed it was the pump as the relay was clicking and was clean but I was not getting power at the pump when I flicked the ignition so it was not priming. A few smart taps with a screwdriver did not free it so he lifted me home.
When we got here I joked it would work again,...sure enough it did! Engine seemed fine but thought had best change pump incase it did it again.
When test drove after fitting it seemed fine but the next day it started to play up very slightly and has got worse, much worse, since.
Going outside to check those plugs...
Don't know why pump stopped working. The AA guy agreed it was the pump as the relay was clicking and was clean but I was not getting power at the pump when I flicked the ignition so it was not priming. A few smart taps with a screwdriver did not free it so he lifted me home.
When we got here I joked it would work again,...sure enough it did! Engine seemed fine but thought had best change pump incase it did it again.
When test drove after fitting it seemed fine but the next day it started to play up very slightly and has got worse, much worse, since.
Going outside to check those plugs...
Plugs are dry and good. Light brown in middle, bit of dry coke around outside edge. All exactly the same. Dizzy and leads all re-cleaned and inspected.
It now wants to die even when I dip the clutch on a test drive. Though runs on tickover fine and still holds a steady pink-free beat at 2,3 or 4000 revs when standing. Restarts directly if it does die. It feels like the ignition has been turned off when it faulters and then struggles to get back to regular revs when clutch dropped.
I have noticed a more pronounced 'sucking' sound when I accelerate or decelerate, so airflow meters are again on my strip or replace with spare checklist. Also a very fast clicking from the plenium area when I blip the throttle. This I think could be injectors? Possibly got some crap through the system when booted up the new fuel pump? Would have thought the post-pump filter would have caught any or the FSE boost Valve wotsit, but it's possible I guess. Strange it does not behave the same way though when the car is stationery though if this is the case?
It now wants to die even when I dip the clutch on a test drive. Though runs on tickover fine and still holds a steady pink-free beat at 2,3 or 4000 revs when standing. Restarts directly if it does die. It feels like the ignition has been turned off when it faulters and then struggles to get back to regular revs when clutch dropped.
I have noticed a more pronounced 'sucking' sound when I accelerate or decelerate, so airflow meters are again on my strip or replace with spare checklist. Also a very fast clicking from the plenium area when I blip the throttle. This I think could be injectors? Possibly got some crap through the system when booted up the new fuel pump? Would have thought the post-pump filter would have caught any or the FSE boost Valve wotsit, but it's possible I guess. Strange it does not behave the same way though when the car is stationery though if this is the case?
F908tim said:
I have noticed a more pronounced 'sucking' sound when I accelerate or decelerate,
Hope you got my diagnostic sheet, sorry pressed send this morning then closed laptop screen down before it finished sending.Given description above I'd be looking for induction leak - try and source location of above noise, but brake servo or hose to it could be a problem, particularly if it started after you either left it standing or worked on engine
HTH
Mark
Its not the wiring loom or obviouse problem with the plug connection under the coil, checked all that thoroughly and all still looks clean. I will check the yellow plug under the column but don't think so as ignition works fine even directly after fault.
Thanks for the Cologne sheet Mark...will read up.
Thanks for the Cologne sheet Mark...will read up.
sounds similar to what I had last year...starts up fine, revs up fine if no load, but as soon as you drive it, it doesn't pull cleanly, and wants to cut out. Got progressively worse over about 2 weeks.
I finally traced mine to the hoses between the AFM and the throttle body having a very small split.....taped it up with insulation tapen (then thermal lagged them) and problem solved.
I'd have a good check for any air leaks on the induction side (also include servo vacuum pipe)
Good luck with finding it....
cheers
Ant
I finally traced mine to the hoses between the AFM and the throttle body having a very small split.....taped it up with insulation tapen (then thermal lagged them) and problem solved.
I'd have a good check for any air leaks on the induction side (also include servo vacuum pipe)
Good luck with finding it....
cheers
Ant
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