4.3L won't turn over after conversion from SCPI to MFI injection - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


GMC/Chevrolet Truck/SUV When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

Reply
 
 
 
Thread Tools Search this Thread
Old 11-23-2014, 07:00 PM   #1
Retired Administrator

True Car Nut
Thread Starter
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default 4.3L won't turn over after conversion from SCPI to MFI injection

Converted the 1998 S10 from SCPI to MFI fuel injection today. I went to turn it over to test the work and the engined crank for a split second and stopped.

The electric appears to be working- the radio and blower motor are working. The fuel gauge and temperature gauges have swung all the way to the fight, showing over filled fuel and temp way past overheating.

The only thing I can think of is I "vapor locked" the engine when I cleaned the carbon of the upper intake manifold (wear the injectors plug in) with a can of seafoam and carb cleaner. Much of it drained into the manifold- likely a can worth of seafoam.

Any thoughts? I sense I can take out the plugs and try and turn over, but wanted some input from forum members- maybe I have another issue.
GunsOfNavarone is offline   Reply With Quote
Old 11-23-2014, 07:07 PM   #2
Senior Administrator








Certified Car Nut
 
Mike's Avatar
 
Join Date: Jul 2003
Location: Horseheads, NY
Posts: 15,649
Thanked 1,001 Times in 777 Posts
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

You mean you hydrolocked it cleaning it? Yes, very possible. Pull all the plugs, press the accelerator to the floor so the PCM sees at least 95% throttle(this turns the injectors off) and crank away for about 30 seconds. Reinstall plugs, restart. Vrooom.
Mike is offline   Reply With Quote
The Following User Says Thank You to Mike For This Useful Post:
GunsOfNavarone (11-23-2014)
Old 11-23-2014, 07:13 PM   #3
Retired Administrator

True Car Nut
Thread Starter
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default

Thanks Mike, will try it in about an hour....
GunsOfNavarone is offline   Reply With Quote
Old 11-24-2014, 10:37 AM   #4
Retired Administrator

True Car Nut
Thread Starter
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default

Pulled the plugs, turned it over for 30 seconds, put in new plugs and tried to start it. The hydrolock problem has gone away.

Now it just turns over, no signs of it wanting to fire. I thought I caught the problem, I pulled the wire from the coil to the distributor cap to prevent the spark plug wires from getting power during the hydrolock cleaning. Plugged the coil wire back together- same problem.

I don't think the new plugs are fowl. Went back and checked all the connectors that were separated when I pulled the upper manifold, everything looks connected.... The only issue I can see is the temp gauge is showing well past 250 degrees. Maybe a pinched wire?

Time to check for spark.....
GunsOfNavarone is offline   Reply With Quote
Old 11-24-2014, 12:16 PM   #5
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

how about the engine ground?clean and tight?
jwfirebird is offline   Reply With Quote
Old 11-24-2014, 01:05 PM   #6
Retired Administrator

True Car Nut
Thread Starter
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default

Justin,

I am on my way to Advance Auto to pickup a inline spark tester. Other than the coolant temperature gauge, the rest of the instrument cluster electronics are functioning. Why do you think I may have an engine ground issue?
GunsOfNavarone is offline   Reply With Quote
Old 11-24-2014, 02:08 PM   #7
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

the sensor for the temp, and the coil, and a bunch of other things ground through the engine ground.
jwfirebird is offline   Reply With Quote
The Following User Says Thank You to jwfirebird For This Useful Post:
GunsOfNavarone (11-24-2014)
Old 11-24-2014, 02:35 PM   #8
Retired Administrator

True Car Nut
Thread Starter
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default

Just tested for spark- looks ok. I was guessing cold be a coil, or even a crankshaft position sensor. I smell fuel and have a newer Delphi fuel pump.....

Back to the drawing board.
GunsOfNavarone is offline   Reply With Quote
Old 11-24-2014, 06:11 PM   #9
Retired Administrator

True Car Nut
Thread Starter
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default

Had a new OEM coil, went ahead and installed it, and the S10 started up. I drove the S10 30 miles and no issues.

My concern is something Justin mentioned. When the truck started, the temp gauge showed normal. When the truck would not start the temp gauge read well past the overheating point. Justin mentioned a bad engine ground can cause gauges to read like this.

Heck, I might replace the crank position sensor, I have a new one laying around, just start replacing ignition related items so it can make troubleshooting of a intermittent problem a little easier...
GunsOfNavarone is offline   Reply With Quote
Old 11-25-2014, 08:15 AM   #10
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

i would clean the ends of the big cables, but i wouldnt be replacing stuff that works
jwfirebird is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Windshield Wipers wont turn off, no Turn Signals, door lock won't work, etc methatswho Pontiac 3 03-15-2015 09:26 PM
won't turn over Stitch 2000-2005 25 01-09-2008 08:40 PM
Car won't turn over Cyclone76 1992-1999 3 10-31-2004 03:23 AM
My car won't turn over!!! Help! Str8pimpin 1992-1999 17 09-27-2004 05:44 PM
Sometimes won't turn over. A Bonnie Canuck 1992-1999 7 10-03-2003 05:19 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 08:13 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.