| [ Total Views: 873 | Total Replies: 20 | Thread Id: 84702 ] |
|
|
 ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on July 9th, 2010 at 08:12 AM |
|
|
Ignition coil
Can a coil be breaking down intermttently? I've only had them work or not work. I can get the engine to start but not run. It's FI and I've
replaced the double relay and the fuel pump is working so I've ruled that out but with someone else cranking the engine there seems to be no spark at
the plugs>
|
|
|
 matberry
Super Moderator
Go hard or go home
Posts: 8114
Threads: 134
Registered: March 7th, 2006
Member Is Offline
Location: Cooroy Qld
Theme: UltimaBB Pro Blue
Mood: enjoying waving at all my Kombi buddies from my T3
|
| posted on July 9th, 2010 at 08:35 AM |
|
|
Coil or it's connections can give intermittant probs Barry. Chuck om another to test it, but make sure the connections are good as you go.
When it starts, it doesn't run at all, so just fires on a cylinder or two??? Doesn't sound like ign. but you can check spark as you've said, maybe
coil HT lead is a prob???
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
 |
|
|
Sides
A.k.a.: Dave Sidery
Veteran Volks Folk
Posts: 2220
Threads: 59
Registered: May 20th, 2007
Member Is Offline
Location: Brisbane
Theme: UltimaBB Pro Blue
Mood: Need... more... shed... time...
|
| posted on July 9th, 2010 at 09:27 AM |
|
|
Also maybe check the earth strap from the trans to the chassis.
Have heard of cases where the strap was busted and the engine basically only earthed through the clutch and throttle cables... it'd fire once or
twice but that was it.
VWDCQ vice pres & web dude - vwdcqinc.org.au
Join a car club - get car peeps
My toys
'70 Hillclimb Bug 'Jezebel' w/- Haltech EFI - http://bit.ly/VwTNtQ
'60 KG Coupe - resto kinda started
01 New Beetle - gf's car, but I turn the spanners |
|
|
ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on July 9th, 2010 at 10:58 AM |
|
|
I thought it would be the fuel pump circuit as the pump comes on only when the starter motor runs then the double relay keeps the pump running when
the starter is no longer needed. The engine starts up then dies as if the pump has stopped, so I checked first that the pump works, it does. I checked
that I was getting a spark at the points,I was but when I had someone turn the engine over there was no spark at the plugs. All that happened was one
day I drove to work-all fine, the next morning nothing, everything checked out fine, just wouldn't start, like no spark. I replaced the double relay
and it started so I used it for work, no problems, drove home. Next morning nothing. I have another new double relay but I may go get another coil as
they're not expensive and try that but I'm very tempted to get rid of the FI all together except that when it's running it is super
smooth.................for a VW!
|
|
|
matberry
Super Moderator
Go hard or go home
Posts: 8114
Threads: 134
Registered: March 7th, 2006
Member Is Offline
Location: Cooroy Qld
Theme: UltimaBB Pro Blue
Mood: enjoying waving at all my Kombi buddies from my T3
|
| posted on July 9th, 2010 at 12:21 PM |
|
|
Before you buy a coil, go step by step with the coil output. You said the points were sparking but no HT output, where did you test that. While you
test the points, the coil should output, so at the same time, hold the coil HT lead near an earth, arc the points, (preferrebly by rocking the engine
with the points just opening and closing), test for spark at the dissy end of the coil H/T, etc.
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
|
|
|
68AutoBug
A.k.a.: Lee Noonan
Aircooled Master
Beetle Restorer - Experience over 138% - YIKES --
Posts: 11654
Threads: 449
Registered: August 31st, 2002
Member Is Offline
Location: SCONE in UPPER HUNTER VALLEY NSW
Theme: UltimaBB Pro Yellow
Mood: Really Mentally Ill - all of the time -
|
| posted on July 9th, 2010 at 02:17 PM |
|
|
| Quote: | Originally
posted by ancientbugger
Can a coil be breaking down intermttently? I've only had them work or not work. I can get the engine to start but not run. It's FI and I've
replaced the double relay and the fuel pump is working so I've ruled that out but with someone else cranking the engine there seems to be no spark at
the plugs>
|
Hi
Yes, coils do break down internally, or the top can crack..
so, something is happening at the points...
so, I presume Your spark is there..?? maybe..
but not getting out of Your dizzy..??
or.. not getting to the dizzy, via the high tension leads...
high tension leads , [not the ultra expensive ones] can break down or short out..
test each lead with a multimeter...
check Your high tension lead is pushed right in at the coil and at the distributor..
PS: I do carry a spare coil... lol
cheers
LEE
- [size=4]Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY--- [/size]
|
|
|
vlad01
Compulsive Aussie Vee Dubber
Posts: 4270
Threads: 109
Registered: June 3rd, 2010
Member Is Offline
Location: Kyneton, VIC
Theme: UltimaBB Pro Blue ( Default )
Mood: Side ways
|
| posted on July 9th, 2010 at 02:26 PM |
|
|
yep coil can and do break like that. a few types of failures are:
Primary coil open circuit.
Primary coil short circuit.
Secondary coil open circuit.
Secondary coil short circuit.
Sounds like you have a problem with the secondary as you are lacking output when clearly you have current draw on the primary.
Time for a new coil.
71 notchback,
Past owner of, 70 NB, 73 SB and 72 FB TLE |
|
|
ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on July 9th, 2010 at 02:59 PM |
|
|
I've checked all the leads and they're good, the distributor and cap are fine. I haven't checked the HT from the coil to the dist. so I'll pop out
and check that now, I'll also change the points while I'm there and see what happens but what keeps on throwing me is it still feels to me like a
fuel thing-forget about the lack of spark for a moment but it'll fire up on all cylinders and then die like the circuit in the double relay isn't
keeping the pump going.
|
|
|
grumble
Son of Jim - Creator of Good
Posts: 2668
Threads: 53
Registered: June 10th, 2008
Member Is Offline
Location: Taree
Theme: UltimaBB Pro Blue ( Default )
Mood: happy all the time
|
| posted on July 9th, 2010 at 04:42 PM |
|
|
Are the points burnt a blue colour,it may be a condenser as they will break down intermittently,but grom your description it does sound like fuel
supply,on the main fuel rail there is a 7mm bolt in a T remove the screw and fit a fuel pressure gauge over this fitting,this will tell you if the
pump is stopping and you can work from there.Cheers Les
|
|
|
ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on July 9th, 2010 at 05:25 PM |
|
|
That sounds like a good idea Les.
|
|
|
ernie norley
Commited Dubber
Posts: 64
Threads: 13
Registered: January 8th, 2009
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on July 9th, 2010 at 05:25 PM |
|
|
Gday all does the car run a balast resistor it maybe wired incorrectly when you let it return off start and it stops theres a wire unpluged for ign
side of resistor this is my thoughts on it starting but not running
Ernie
|
|
|
ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on July 9th, 2010 at 06:04 PM |
|
|
Ernie it does have a ballast resistor on the coil but that has never been unwired(?). Would it cause any damage to anything if I wired it the other
way round. In the past and present with all my cars the coils have never used one but this came with one and I've never had a problem so saw no
reason to change it.
|
|
|
grumble
Son of Jim - Creator of Good
Posts: 2668
Threads: 53
Registered: June 10th, 2008
Member Is Offline
Location: Taree
Theme: UltimaBB Pro Blue ( Default )
Mood: happy all the time
|
| posted on July 9th, 2010 at 06:17 PM |
|
|
is the resistor wire burnt out?
|
|
|
matberry
Super Moderator
Go hard or go home
Posts: 8114
Threads: 134
Registered: March 7th, 2006
Member Is Offline
Location: Cooroy Qld
Theme: UltimaBB Pro Blue
Mood: enjoying waving at all my Kombi buddies from my T3
|
| posted on July 9th, 2010 at 06:31 PM |
|
|
Or put a test light accros the fuel pump terminals, will proove it gets continuous supply.
Matt Berry Motorsports...air cooled advice, repairs and mods Ph 0408 704 662
OFF-ROAD,CIRCUIT,DRAG,STREET,ENDURANCE
|
|
|
ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on July 10th, 2010 at 12:09 PM |
|
|
AND THE WINNER IS.....................none of you! It was an air leak! Where the intake boot connects to the plenum chamber it had slipped off but not
until I had given everything a thorough shake,pull or just a bloody good talking to. I'n no expert with FI but it all seems arse about face with the
symptoms, when there's an air leak it runs slower or in this case not at all. In Pauline Hansons famous words "Please explain?" BTW she's running
sweet again.
|
|
|
68AutoBug
A.k.a.: Lee Noonan
Aircooled Master
Beetle Restorer - Experience over 138% - YIKES --
Posts: 11654
Threads: 449
Registered: August 31st, 2002
Member Is Offline
Location: SCONE in UPPER HUNTER VALLEY NSW
Theme: UltimaBB Pro Yellow
Mood: Really Mentally Ill - all of the time -
|
| posted on July 10th, 2010 at 01:38 PM |
|
|
| Quote: | Originally
posted by ancientbugger
AND THE WINNER IS.....................none of you! It was an air leak! Where the intake boot connects to the plenum chamber it had slipped off but not
until I had given everything a thorough shake,pull or just a bloody good talking to. I'n no expert with FI but it all seems arse about face with the
symptoms, when there's an air leak it runs slower or in this case not at all. In Pauline Hansons famous words "Please explain?" BTW she's running
sweet again.
|
thanks pauline...lol
Must have been a BIG leak..??
although Fuel Injection is like rocket science... lol
everything balanced..??
LEE
- [size=4]Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY--- [/size]
|
|
|
ernie norley
Commited Dubber
Posts: 64
Threads: 13
Registered: January 8th, 2009
Member Is Offline
Theme: UltimaBB Pro Blue ( Default )
|
| posted on July 10th, 2010 at 01:58 PM |
|
|
Gday all glad to hear you have it running nothing worse than not knowing where to start. then finding an unrealated symptom to be the cause have a
nice weekend
Ernie
|
|
|
bajachris88
A.k.a.: Chris Leete
23 Windows of Awesome
The international telephone dialing code for Antarctica is 672.
Posts: 6661
Threads: 534
Registered: April 8th, 2005
Member Is Offline
Location: Tanah Merah, SE-QLD
Theme: UltimaBB Pro Blue ( Default )
Mood: A bee bit ma' bottom, now ma' bottom's big!
|
| posted on July 10th, 2010 at 05:50 PM |
|
|
An air leak makes perfect sense. an FI system with a AFM (air flow meter) as opposed to a MAP will stall instantly after start up. Its the central
main component for the computer to make judgement on air/fuel ratios based on teh programmed air/fuel curves. Its like ripping a heart out of a human,
it doesn't work well lol (don't try that one at home kids!!) 
IE: ur afm wouldn't have registered air flow as it would be sucking through the vac leak (near complete bypass if large enough). the start up
injection does its job, then it just dies over because it doesn't register any air flow (or very little) and adjusts the fuel mixture to suit the
wrong air flow.
And if its next to no air flow in the afm, it'll spit out next to no fuel to suit. (like a fuel cut off at the injector)
(ô_!_/ô) (ô_!_/ô)
69' baja: kombi box, thing spindles, irs, disc front, type 3 rear drums, 2 inch lift kit, 31x10 rears. 
New engine in process: 94mm p&bs, 74mm C/w chomol Crank, 35.5x39 SP heads, turbo. Wierd combo, hopeful torque monsta! |
|
|
ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on July 10th, 2010 at 06:22 PM |
|
|
Where the elbow fits over the lip of the plenum inlet there's not a great deal of overlap so when the hose clip tightens up it slips up and off. It
was only when I actually made the mad dash from switching on then back to the engine I actually heard the hiss before the engine died. All good
now
|
|
|
grumble
Son of Jim - Creator of Good
Posts: 2668
Threads: 53
Registered: June 10th, 2008
Member Is Offline
Location: Taree
Theme: UltimaBB Pro Blue ( Default )
Mood: happy all the time
|
| posted on July 10th, 2010 at 06:29 PM |
|
|
| Quote: | Originally
posted by bajachris88
An air leak makes perfect sense. an FI system with a AFM (air flow meter) as opposed to a MAP will stall instantly after start up. Its the central
main component for the computer to make judgement on air/fuel ratios based on teh programmed air/fuel curves. Its like ripping a heart out of a human,
it doesn't work well lol (don't try that one at home kids!!)
IE: ur afm wouldn't have registered air flow as it would be sucking through the vac leak (near complete bypass if large enough). the start up
injection does its job, then it just dies over because it doesn't register any air flow (or very little) and adjusts the fuel mixture to suit the
wrong air flow.
And if its next to no air flow in the afm, it'll spit out next to no fuel to suit. (like a fuel cut off at the injector)
|
They also split the rubber and again run like crap.Glad you have it sorted out.Les
|
|
|
ancientbugger
Custom Title Time!
Posts: 1986
Threads: 191
Registered: March 24th, 2004
Member Is Offline
Location: sunshine coast
Theme: UltimaBB Pro Yellow
|
| posted on February 2nd, 2011 at 09:54 AM |
|
|
You've have to love this forum, this has just happened again and I couldn't remember what caused it last time but a search and sorted!
|
|
|
