'85 QV cranks - won't start | FerrariChat

'85 QV cranks - won't start

Discussion in '308/328' started by myronx19, May 24, 2020.

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  1. myronx19

    myronx19 Formula Junior

    May 27, 2012
    653
    Toronto, ON Canada
    Full Name:
    Myron Samila
    Hi all - I searched the forum but couldn't find an answer that fits these symptoms.

    I worked on my friend's Canadian spec '85 QV the other day. The car cranks fine but would intermittently "not start", which he said playing with the key (on/off) a few times would resolve it and then it would start and run.

    He diagnosed it as the ignition switch being bad - seems logical, and since he had a new one - I changed it for him. That didn't cure the issue and I wasn't surprised (it's wired right!)

    On the day I picked it up, it would not start at all - cranks, you can smell fuel but no start (no spark). There is power at the coils (used a test light), but no spark at the plugs. Interestingly, the fuel pump relay clicks like mad while cranking - but I don't know if that's normal - that isn't the issue though, he said it always did this.

    So after changing the switch - same issue - it cranks, smell fuel, no start, no spark All fuses check OK (test light) on an original fuse panel. I swapped fuel pump and one other relay with others that are identical just as a process of elimination. No go, still smell fuel but no spark, no start.

    At this point - there is power at the coils, but no spark (no "signal" to the coils). At this point, best case is that the crank trigger sensor is bad (I've read there are three in total? - but if one was bad, I would think one bank would fire). Worst case - the ECU is bad?! I didn't have a service manual handy, would have been a lot easier. I wanted to reach out and see if anyone has had a similar issue. Automotive electrical is what I know best, lol... so I thought this would be a piece of cake. Since my friend was busy all day, the plan was that I was going to spend the afternoon driving it after fixing it! ha! Instead I had to drive my X1/9, lol..

    Fuel pump is good
    Coils are good (there's power)
    Cranks fine
    Fuses all check out fine (and connection on the OE fuse panel, yikes.. not the best design but that's a whole other thread!)
    No spark
    Maybe the 666 is a sign..

    It's a nice car - 42K kms, great shape! Love this thing!

    Thanks!

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  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
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    Jan 11, 2001
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    #2 Steve Magnusson, May 24, 2020
    Last edited: May 24, 2020
    It has two TDC flywheel sensors -- if one fails, one bank of ignition fails.
    It has one RPM (engine speed) Flywheel sensor -- if that fails, both banks of ignition fail.
    The functional test for the RPM Flywheel sensor is that it should measure ~2V AC between the two leads when plugged in and the starter motor is cranking the engine. From the 308QV OM (if your friend has one):
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  3. miketuason

    miketuason F1 World Champ
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    Feb 24, 2006
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    Have checked inside the distributor caps for something obvious like crack caps or broken rotors or maybe missing or worn out spring loaded carbon contact?
     
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  4. 308 milano

    308 milano F1 Veteran

    Jan 15, 2007
    5,257
    Montana
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    #4 308 milano, May 24, 2020
    Last edited: May 24, 2020
    Would also pull the plugs and dry them out. (small butane torch works well for this) Pull the large Plenum hose and make sure you don’t have a bunch of fuel setting in the throttlebody and lower portion of the fuel distributor.
    I’m 650 miles from home at the moment so can’t review my trouble shooting notes but there was another relay I believe was called something like control start relay? That I also swapped while troubleshooting my QV. Might give that one a shot also. If you end up changing crank sensors it’s not a hard job at all.
     
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  5. moysiuan

    moysiuan F1 Rookie
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    Nov 1, 2005
    3,628
    Canada
    Most of the spark trouble areas would not affect all cylinders, the car would start or at least cough if only certain cylinders were affected. With two ecu's essentially running each bank as a separate 4 cylinder engine, one computer failure would still probably have the car cough and catch if not outright start. The rpm sensor would be the exception that as noted affects all cylinders.

    But are you sure there is no spark at the plugs? How did you determine that?
     
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  6. johnk...

    johnk... F1 World Champ
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    I just clicked this thread to say that. :)
     
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  7. 308 milano

    308 milano F1 Veteran

    Jan 15, 2007
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    Very good points. With both My QV ‘s, if it is flooded it won’t fire at all until the plugs were pulled, dried or changed out. Would make you think that it wasn’t getting any spark (or weak spark) for sure.
     
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  8. Tonksy1

    Tonksy1 Karting

    Jun 21, 2016
    91
    New Zealand
    I've had problems in the past with the large white electrical plug that feeds the crank sensors through the body work in the engine bay. Water can get into it and corrode the contacts. Give it a good clean. Good luck.

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  9. myronx19

    myronx19 Formula Junior

    May 27, 2012
    653
    Toronto, ON Canada
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    Myron Samila
    Thank you! (and the other replies as well)

    Interestingly, I charged the battery overnight and the car started the next day. Just to make sure it's not intermittent, I took the car on a day long "test drive" and it worked flawlessly. Doesn't seem logical that the battery was strong enough to crank, but no spark. (keep in mind, I was cranking for a while so I did run it a bit flat trying to get it to start before I changed the switch) BTW it's a new Optima yellow top battery, and I've had three Optimas fail in 5 years on a different car. I like AGM batteries, just not those!

    Ah - and to answer how I determined there's no spark? Took a spare spark plug and the boot off and held a plug on the valve cover. I also have an inline spark tester that mounts to the extender or the plug directly (good for determining if there's a bad extender.) Pretty easy. I also have an inductive pickup tester, but I didn't use that.

    I'll rig something up to plug into the diagnostic socket - that's handy. Thank you. If it happens again, perhaps the flywheel sensor or connectors in between are corroded. For now, the car seems to be working flawlessly and I really enjoyed driving it all day. I didn't want to give it back! :)

    Thanks guys - I'll update the post if it happens again and what the solution was.

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  10. miketuason

    miketuason F1 World Champ
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  11. myronx19

    myronx19 Formula Junior

    May 27, 2012
    653
    Toronto, ON Canada
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    Myron Samila
    On side note: one thing I noticed after the new switch supplied from Superformance UK went in was that I noticed "arc" noise in the switch housing when switching the key to the OFF position.

    This is "normal" and how bad it is can sometimes depend on how fast you turn the key (slower is usually worse). There are a lot of inductive loads (relays & coils) going through the switch, and when you turn it off - you can sometimes hear it - slightly exaggerated by the switch housing design (it's like a hollow can). You really need to be listening though, but it is happening.

    Anyway, anecdotally - this is probably why the original switch failed after ~40K kms. I'll crack the old one open just to take a look at the contacts, but I wouldn't be surprised to see tons of carbon build up and damaged contacts. He did spray WD40 into the key lock (thinking it would clean the contacts, surprisingly it made its way into the switch!) - and well.. WD40 is flammable, so that arcing could have made a nice little toasty fire. Most contact cleaners are flammable as well - so don't spray anything in there!

    Switch replacement was pretty straightforward - flat head screwdriver is required, the bottom one is easier to get at - the top one required a 90 degree screwdriver to get it started, and then a thin one at an angle. Wires must be removed before removal - you need small fingers to get in there. Putting the screws back in is tricky - but I managed fine. Make sure the spade connectors seat well - the white one has two wires in a single spade, and that wire was tricky to maneuver and finally seat. Helps that I have small hands and fingers! (lol!).
     
  12. myronx19

    myronx19 Formula Junior

    May 27, 2012
    653
    Toronto, ON Canada
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    Myron Samila
    Oh sweet!!! Love it! I love the Scorpion (as you probably know, it shares the basic suspension design of the X1/9!, and a lot of other parts as well!) The interiors are much higher quality in the Lancia than the X1/9 - and I love the design as well (especially the seat design, they're really cool). A local guy stuffed a new Abarth 500 motor into his X1/9 (boosted to 24lbs!) and I always thought it would be easier to swap into a Scorpion, albeit not for the purist - but over 200 HP in that car would be pretty interesting!

     
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  13. Dr Tommy Cosgrove

    Dr Tommy Cosgrove Three Time F1 World Champ
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  14. johnk...

    johnk... F1 World Champ
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    #14 johnk..., May 26, 2020
    Last edited: May 26, 2020
    More like "cute". Chick car back in the day. My niece had one. No self respecting, hormone bleeding male would be seen in one. :)

    ---------------------------------------------------------------------------------- (No, that's not her.)\/

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  15. Dr Tommy Cosgrove

    Dr Tommy Cosgrove Three Time F1 World Champ
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    I actually knew a girl that drove one in college. She was also Italian.
     

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