Ok, got this stock rebuild back together and it just will not run. I have spark, fuel, and compression. Cam sensor has been set, and crank sensor gapped. Every couple of revolutions I get an intake backfire (blew off vaccum hose once), but thats about it... I'm out of ideas at this point, so any help would be greatly appreciated! It acts like a carb-ed & distributed car with the timing off about 90* ...
cranks, but doesn't fire...
- Thread starter benf8706
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Sounds like the cam sensor is not set right.
Thanks for the reply, I'll head out to the garage to make dead sure, set using Cam Sensor Information but I'll check again... previously tried two different cam sensors using this method (one new, one from running car) if that helps at all
Just a Six??
OK! Who Farted??
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Not to be an azz but check your plug wires that they are on correctly. Happened to others before. Also, are your coil & module known good or can you swap them out with someone?
Not saying this is your problem but is worth taking a look at.
I chased a running rough / then a no start problem until i happened upon this thread, i'll post it below. I checked my balancer reluctor ring and sure enough it had moved far enough to make it out of time, the engine would eventually backfire and not start. I had been checking the cam sensor setting,crank sensor gap,sparkplugs,wires,fuel reg.,etc.
Read the post in this thread by JDEstill.
http://www.turbobuick.com/forums/general-turbo-buick-tech/194487-ignition-timing-variance.html
John :smile:
I chased a running rough / then a no start problem until i happened upon this thread, i'll post it below. I checked my balancer reluctor ring and sure enough it had moved far enough to make it out of time, the engine would eventually backfire and not start. I had been checking the cam sensor setting,crank sensor gap,sparkplugs,wires,fuel reg.,etc.
Read the post in this thread by JDEstill.
http://www.turbobuick.com/forums/general-turbo-buick-tech/194487-ignition-timing-variance.html
John :smile:
You did have the #1 cylinder on the compression stroke, right?
If not the cam sensor could be 90* out.
I always take the drivers side valve cover off and make sure both valves on #1 cylinder are closed and the intake valve on #3 cylinder is closed and #5 exhaust valve is closed that way i know #1 cylinder is at TDC on the compression stroke. Then move the balancer to 25*ATDC to install the cam sensor.
John :smile:
thanks for the replies guys-- just checked the wires and swapped out with a module from a running car - still nothing
re-re-checked that the cam sensor is installed correctly (#1 @ TDC on compression) , had a look at the valve positions also everything looked kosher
interesting idea on the balancer ring whitehot1 ,, sounds like its definately worth a shot here after work
thanks again !
ok pulled the balancer and had a look at the balancer ring - its maaaaybe 1/16" off... I'm wondering if this is enough to cause my trouble? I was almost hoping that the ring was like an inch off so it would explain why it seems like its sparking at the wrong time.. still puzzled
on a side note, there is no SES light with key on and ports A and B jumped on the diagnostic plug-- when jumped the fan somes on, and thats it... i followed Malfunction Codes Reference
There is a lot of good information and troubleshooting charts and tips on this website.
http://www.vortexbuicks-etc.com/
John :smile:
http://www.vortexbuicks-etc.com/
John :smile:
84BuickGNYorkPA
Daily Driving Buick V-6 Turbo's 1979 - Present
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I think you found your problem, no SES light means the ecm is not getting power. Put a voltmeter on the ecm power wire going into the ecm and check if you have juice. Possible the ecm light is out, you will need to fix this for future trouble shooting.
Chuck
a good point, but I try not to take any of my vehicles (new or classic) to be fixed at a shop if I can help it - I enjoy learning what there is to know about the vehicle, and having the satisfaction of fixing it myself! I'm just new to these Buicks , and a Buick Mechanic (for reference) is hard to find around here... only ONE GM mechanic in town said that "he seen one once" in the garage in the 90's
anyways... bad ECM = no injector pulse correct? because i'm thinking the SES light just might be burnt out since NOID light is flashing happily on all cylinders
25* after, or 1.45"
ok, so I'm not sure how this is possible but the clamp for the cam sensor wasn't tightened and my buddy was cranking motor over while I was messing with some wires and i accidentally bumped the cam sensor maybe 5* clockwise and it magically fired up... so i stared at it for a minute and rotated it back-- it shut right off... I'm just wondering how this is possible lol
Glad you got it fixed and that it wasn't anything major.
You might want to take a good look at the threads in the hole that the cam sensor hold down bolt goes into and check to see if they are damaged.
It wouldn't be a good thing for that bolt to loosen up and have the cam sensor move while driving down the road.
John :smile:
hey well thanks, at least now by checking EVERYTHING else I know for sure that all my grounds are good and also where all the ECM harness wires trace out to lol -- threads looked good, so I used a very light duty thread locker to keep this from happening again after I set the sensor properly.
