Go Back   DodgeForum.com > Dodge Trucks > Dodge Dakota > 1st Gen Dakota
Sign in using an external account
Register Forgot Password?


1st Gen Dakota '96 & Older Dakota's

Help! '91 Dodge Dakota 4x4 3.9 no spark

Reply
 
 
 
 
Thread Tools Search this Thread
  #1  
Old 01-16-2011, 10:13 PM
adrielkelsick adrielkelsick is offline
Registered User
 
Join Date: Jan 2011
Posts: 4
Default Newb from Spokane, WA

I have recently come into ownership of a 1991 Dodge Dakota 4x4, 3.9L carbureted. 156K, former Dept. of Agriculture vehicle. Looks like ****, the white paint job is half peeled off (I wonder if it was a cheap aftermarket job to make it government white). But it's straight and otherwise seems in good condition. I have owned it for 5 days and it hasn't moved an inch from the guy's yard where I bought it.

No spark. Thought it was as simple as a coil. No. Thought it might be as simple as a pickup coil in the distributor. No. Thought it might be as simple as no fuel. No. Thought it might be the infamous 3-way splice in the wiring harness a little ways from the battery. No. Thinking it's a sensor or the computer, although according to the gentleman from whom I purchased said rig, the computer had been recently replaced. A big reason I'm here is for assistance diagnosing this no spark/no start issue. Hello and help.
This ad is not displayed to registered and logged-in members.
Register your free account today and become a member on Dodge Forums!
Reply With Quote
  #2  
Old 01-16-2011, 10:32 PM
adrielkelsick adrielkelsick is offline
Registered User
 
Join Date: Jan 2011
Posts: 4
Default Help! '91 Dodge Dakota 4x4 3.9 no spark

3.9, carbureted, turns over nice and healthy, distributor spins, no spark at plug wires or from coil. Coil replaced with 2 others, all 3 tested good, no spark at any point. Distributor replaced with another (used) distributor in case pickup coil was bad, no change.

I've never owned a Dodge before, I'm wondering if it's a crank/cam position sensor, but I'm not sure the engine has one - haven't been able to spot one. Are there only cps' in fuel injected engines? Where is the bastard?

Other question: is there a reason NOT to run a wire from the battery positive to the coil? That's how I have my '84 Bronco going because the ignition broke. Granted the '84 is a simpler engine. two oh eight 659 71 three two, please text if you have the answer, I'll check back for replies tomorrow

heeeelp

thanks!
Reply With Quote
  #3  
Old 01-17-2011, 01:23 AM
Crazy4x4RT's Avatar
Crazy4x4RT Crazy4x4RT is offline
Offroad Dakota Moderator
Dodge Forum Moderator
 
Join Date: Aug 2007
Vehicle: 93 Dakota
Location: NM
Posts: 10,828
Default

Are you sure it is carbureted? In 91 it would have been TBI Throttle Body Injection. Yes it could be a cam or crank sensor. First check the check engine codes.
__________________
My Youtube Videos! ----My Photo Albums---Solid Axle Swap ----- Leaf Spring Swap/flip ----2wd-4wd swap

"No truck should ever be lowerd! NEVER" Buy a car if you want it low!
Reply With Quote
  #4  
Old 01-17-2011, 08:31 AM
1969CoronetR/T's Avatar
1969CoronetR/T 1969CoronetR/T is offline
vaffanculo
Dodge Forum Moderator
 
Join Date: Oct 2008
Vehicle: 1969 Coronet R/T - 1969 Mr. Norms Super Bee - 2014 Jeep SRT
Location: Pittsburgh, PA
Posts: 7,833
Default

Welcome to the site. I will move this thread to the first generation Dakota section,
FF
Reply With Quote
  #5  
Old 01-17-2011, 10:04 AM
pashadowops's Avatar
pashadowops pashadowops is offline
Veteran
 
Join Date: Aug 2007
Vehicle: 1995 Dakota
Location: NE PA
Posts: 334
Default

Welcome to the forum!

I don't see where you say you have replaced the wires. I had a similar problem two summers ago and it turned out to be my coil wire got to close to the exhaust manifold and melted the shielding thus causing a break in the carbon fiber. The engine would turn over all day long but it wasn't going to start.
__________________
1995 Dakota Extended Cab 4x4 5.2L Automatic
2003 Jeep Liberty Renegade
2010 Ford Focus SEL
Reply With Quote
  #6  
Old 01-18-2011, 04:39 PM
crazy crazy is offline
Rookie
 
Join Date: Feb 2008
Posts: 53
Default wires

hey i hate to say it but are ya sure ya checked "ALL" the splices in the wires running to the fuze block,,ya gotta unwrap the entire wireing harnes ..theres more than one splice that will cause your problem ,,and even if they aren't completly broken or corroded they still could be causeing your problem ,,i'd make sure all the splices are good before ya go investing in parts ya don't need ,,
crazy
Reply With Quote
  #7  
Old 01-18-2011, 04:48 PM
ne14t ne14t is offline
Rookie
 
Join Date: Jan 2011
Vehicle: 1993 Dakota LE 4x4 3.9L
Location: Vancouver, B.C.
Posts: 50
Default

Thats probably factory paint, my 1993 was factory white and it was great until one day it started flaking off in chunks the size of sheets of paper. Thankfully insurance covered it and the whole truck got a fresh new coat of paint.

In light of your problem though I would check the splices first as mentioned, in our older trucks this seems to be a very common problem, then I would do the wires, you can check your wires for resistance if you have a multimeter you should have a couple hundred Ohms per foot of wire but any bad wire will probably register as infinite resistance.
Reply With Quote
  #8  
Old 01-18-2011, 05:38 PM
bwdakrt's Avatar
bwdakrt bwdakrt is offline
Record Breaker
 
Join Date: Dec 2008
Vehicle: 2001 Dakota R/T
Location: Claremont NC
Posts: 1,201
Default

Your truck definitely doesn't have a carb but as stated before it has TBI injection. Those 2 round thing you see in the top of the throttle body are fuel injectors.

You have a crank position sensor on the back of the engine on the passenger side where the bell housing connects to the engine and the cam position sensor is inside the dist cap...the flat round disc with the 2 wires attached.

Crank Position Sensor
Click the image to open in full size.

Cam Position Sensor
Click the image to open in full size.
__________________


I've learned that pleasing everyone is impossible, but pissing everyone off is a piece of cake.
Reply With Quote
  #9  
Old 01-18-2011, 11:49 PM
adrielkelsick adrielkelsick is offline
Registered User
 
Join Date: Jan 2011
Posts: 4
Default

Thanks for the replies/assistance everyone. My mistake, I guess I do have toilet bowl injection. I put a different distributor in, so my cmps is effectually changed, I gather from bwdakrt's post. I still haven't found the ckps, I'll look again tomorrow.

However, my problem still appears to be no spark from the coil, so anything AFTER the coil is a secondary concern for me at this time. What I have done is run a wire from the +battery post to the +terminal on the coil, and another wire from the -terminal of the coil to the body, using the same ground point as the -bat. cable.

Tried starting it again, once with the wires as described and the original harness wires also connected to the terminals, and once with those DISconnected and only with my jimmy rigged wires. Still no spark either time, just a very hot coil. May have fried it, not sure if they get hot normally or no, I have 2 others though.

Am I wrong in thinking that wiring the coil thus should effectively bypass any bad sensors/computer wiring/etc? Seems to me that if I have a good coil so wired, and am getting fuel, the engine should fire. How it will run will be in question, but at this point I just want some sort of combustion!

Thanks to Dale from Missouri, btw, for your moral support and brainstorming. I don't wanna give up on this truck.

P.S: I am disconnecting the hot wire from the +battery terminal to the coil when not cranking the engine
Reply With Quote
  #10  
Old 03-21-2012, 10:28 PM
dakotaman57 dakotaman57 is offline
Registered User
 
Join Date: Feb 2004
Location: United States
Posts: 4
Default no spark or fuel in cold weather

Hello all, I am new here and need help pls. I am experiencing a similar problem with my 1991 Dodge Dakota 3.9 V6 described in this topic. The only difference is, my truck won't start if the ambient temp is 45F or colder (will turn over fine). Above 45F and it will start fine and run fine. If there was a break in the electrical or bad relay it wouldn't start at all.
The truck has 155k miles and in very good condition, Previous owner replaced the following:
coil, cap, rotor, pick-up coil, plugs, plug wires and ASD relay, checked fuses. no luck. (he was so mad he GAVE me the truck)

One thing I did notice, the ambient temp was warm and the truck started. I turned the truck off. I used the "KEY-ON, KEY-OFF" method to extract any codes in memory. The only codes were "12" (replaced battery) and "55" end of code cycle.
The next morning was very cold and thought I'd try starting the truck. Cranked over fine..... Well, no spark, no fuel = no start. OK, I'll try checking codes again. I noticed the "check engine light" or "maint. reqired" light wasn't showing at all when I turn the key on. So I left it alone most of the day until the ambient temp was warm. About 2:30pm I tried extracting codes again. This time the "check engine" and "maint. required" showed on the instrument, check engine light did it's thing for me with no new codes. and yes, the darn thing started right up! I tried this 3 days in a row. Cold morning=no start=no check engine light(with key on position). Warm afternoon=start right up=check engine light functioning(with key on position)
I'm in the dark on this one.
Thanks all
Peter
Reply With Quote
  #11  
Old 04-18-2012, 02:56 PM
Sunnysky Sunnysky is offline
Registered User
 
Join Date: Apr 2012
Posts: 11
Default No sparks Dakota.

Have you figured out what the problem is?
Reply With Quote
  #12  
Old 04-18-2012, 06:31 PM
volaredon volaredon is offline
Captain
 
Join Date: Apr 2010
Posts: 509
Default

Quote:
Originally Posted by bwdakrt View Post
Your truck definitely doesn't have a carb but as stated before it has TBI injection. Those 2 round thing you see in the top of the throttle body are fuel injectors.

You have a crank position sensor on the back of the engine on the passenger side where the bell housing connects to the engine and the cam position sensor is inside the dist cap...the flat round disc with the 2 wires attached.

Crank Position Sensor



Click the image to open in full size.

Cam Position Sensor
Click the image to open in full size.
No no crank sensor on TBI engines those didnt start til the magnum engines in 92
Reply With Quote
  #13  
Old 04-19-2012, 12:18 PM
Sunnysky Sunnysky is offline
Registered User
 
Join Date: Apr 2012
Posts: 11
Default No sparks.

Mine has the same problem, so far I've changed the crank sensor, distributor's cap & rotor & coil but still no sparks. All splices are checked, now waiting for the camshaft sensor (pickup coil) from the autopart store. Not sure if it, camshaft's, will fix the problem. Mine is 93 dakota, 95000 mile.
Reply With Quote
  #14  
Old 04-20-2012, 06:15 PM
volaredon volaredon is offline
Captain
 
Join Date: Apr 2010
Posts: 509
Default

I just went thru a hair pulling escapade that wound up being a bad TPS on my wife's XJ Cherokee last fall; it never failed to start but it was doing all kind of weird stuff;
About the 2nd thing that I replaced early on was the TPS; no change in symptoms or voltage rfeadings; whether by scanner or multimeter/back probing; so 2 different computers 2 JY wiring harness and 6 months later it wound up the 1st TPS that I installed was bad as well. I kept saying "can't be" because I had changed it once already, and chased my tail all around that stupid sensor and wound up replacing it for the 2nd time and no probems since.

Now I'm not saying that I think your problem in this case is the TPS; (it wont cause a no start; itll start with the TPS unhooked but it wont run right))
but what I AM saying is that just because you replaced it dont mean you got a good part to replace it with; got a scanner?
Reply With Quote
  #15  
Old 04-21-2012, 09:50 PM
Sunnysky Sunnysky is offline
Registered User
 
Join Date: Apr 2012
Posts: 11
Default

I'm wondering about the crankshaft sensor I replaced. The new part looks a little shorter than the original one. I am't sure will make any different? It looks and fits right in but a little shorter. Any suggestion?
Reply With Quote
  #16  
Old 04-22-2012, 11:07 AM
adrielkelsick adrielkelsick is offline
Registered User
 
Join Date: Jan 2011
Posts: 4
Default

The problem was a roasted computer.
Reply With Quote
  #17  
Old 04-22-2012, 01:05 PM
Sunnysky Sunnysky is offline
Registered User
 
Join Date: Apr 2012
Posts: 11
Default

adrielkelsick;2769653]The problem was a roasted computer


Any recommend for place to buy new PCM, I'll try that route?
Reply With Quote
  #18  
Old 04-23-2012, 05:31 AM
JR318's Avatar
JR318 JR318 is offline
Veteran
 
Join Date: Mar 2012
Vehicle: 95 Dakota clubcab slt 2wd 5.2magnum
Location: Upstate South Carolina
Posts: 423
Default

[QUOTE=Sunnysky;2769458]I'm wondering about the crankshaft sensor I replaced. The new part looks a little shorter than the original one.

If the new sensor is shorter than there is a good chance it will not read properly. The sensor is a halleffect switch the reads on off on off etc. If the new one is to short it will not read at all. You should be able to test the new one to make sure it is reading with a digital meter. When you test it you will have to back probe the wires( not sure what two wires the are without looking at a schematic) with the key on and slowly rotate the engine. It should read no voltage then around 5 volts then 0 volts then 5 volts again.
__________________
95, Ext cab, 318, 2wd, Auto, Mopar Performance PCM, 50mm Fastman TB, Shorty Headers, HHR EFan, Under drive pulley, Spectre air cleaner, Spectre crankcase breather, Flowmaster 40 series, Removed Cats, 180 thermostat, Tinted tails, Painted dash and trim, LED interior lighting, Pioneer CD Player, 850 watt amp, 10" sub, Ultra 50/51 wheels.
Reply With Quote
  #19  
Old 04-23-2012, 01:35 PM
Sunnysky Sunnysky is offline
Registered User
 
Join Date: Apr 2012
Posts: 11
Default

Thanks for your suggestion, I'll check out.
Reply With Quote
  #20  
Old 04-24-2012, 09:57 PM
volaredon volaredon is offline
Captain
 
Join Date: Apr 2010
Posts: 509
Default

are we sure the truck is a '91? If it is it should not even HAVE a crank sensor! Or is it an early 92 with a production date in late 91?? Just because the truck was built in calender year '91, dont mean it is a 91 model;
91 should be an "LA" series engine with TBI.
Reply With Quote
Old 04-24-2012, 09:57 PM
 
 
 
Reply




Tags
3.9, carbureted, carburetor, cps, newbie, no spark, sensor

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

Forum Jump

Join DodgeForum
Advertising

Featured Sponsors
Vendor Directory
Our Sponsors
All times are GMT -4. The time now is 07:49 PM.

Internet Brands, Inc.


Contact Details & Emails