2012 Ram 1500 cranks but wont start.

90

Asked by 74Ramcharger Feb 28, 2019 at 12:48 AM about the 2012 RAM 1500 Big Horn Crew Cab 4WD

Question type: Maintenance & Repair

Fuel pump comes on with ignition.  Starter fluid in the intake will make it fire for
a couple seconds.  I can't find a port for testing the fuel pressure anywhere but
when I released the connector behind the engine it sprayed gas everywhere so
it has at least some fuel.

12 Answers

420

Pull one coil off put a spark plugs and in it then turn it over see if your getting spark if not your camshaft sensor is bad.

2 people found this helpful.
90

I'll try that but it runs on starter fluid, wouldn't that mean its getting spark?

2 people found this helpful.
420

I apologize 74 I was answering another one and apparently I got onto yours so if it's running off for starting fluid I mean just not getting any fuel so it but you can hear the pump run and fuel comes out where the connector is then if you can disconnect the whole fuel rail from your fuel injectors and turn the key on and make sure to feel it flowing all the way through there are none of the passages are blocked then take take your fuel injectors and clean them with carburetor cleaner or any kind of cleaner like that just spray down in there to try to clean them out and see if that right there will help you if not let me know and we'll continue to look else where can we find the problem

2 people found this helpful.
90

I replaced the whole fuel line from the tank to the fuel rail with an aftermarket one that has a fuel pressure gauge. It's reading a little over 50psi right at the fuel rail. I will remove the rail and injectors next and try your solution. Thanks

1 people found this helpful.
90

I checked the resistance on the injectors and they all were the same. I removed the fuel rails and the injectors, they look new. It only has 24,000 miles on the engine. I did test the voltage on the injectors based on a youtube video they are supposed to have 12v to them with ignition on. They do not. I tested using a voltmeter with the negative wire on the battery post and the positive stuck into the injection connector. It showed 0.2v I also tried checking continuity between the injector ground wire and battery negative while cranking and it did not get any. I connected a scan tool to the odb port and there is one error about an 02 heater low voltage but it says its a stored error so I'm not sure if thats actually from my car or the one before me (I borrowed it from autozone) I'll need to try and find a manual for it to see if I can dig deeper.

1 people found this helpful.
60

Also start from your battery and trace your wiring harness. From what you say it's an electrical problem possibly a broke ground wire or a bare hot wire.

3 people found this helpful.
90

I removed the cover on the wire harness from the engine all the way back to the fuse box and all the wires look good. There are no breaks in the wires and the cover was intact before I took it off. There is one wire that feeds all the injectors so I tried hooking that directly up to 12 volts while cranking just to see if it was a power delivery problem but it still didn't fire. I think the computer isn't closing the circuit like it's supposed to. I did notice that there is a "no bus" message on the dashboard but after a ton of reading google results on that code, none match my symptoms. There is also a red lightning bolt on the dash. I read that might be the throttle system so I will try and do the reset on that. I realized I never posted what happened before this. The truck sat for over a year in a garage with no battery. I dumped the gas, put a few gallons of new gas and a new battery and thats where im at now.

1 people found this helpful.
420

74 in you research have you come across anything that says you can follow a procedure to allow the vehicle to relearn different parameters? I run into something similar on an Infinity and had to help the computer to relearn the gas pedal ( where idol was and wide open was). Also can you spray starting fluid in the intake and put the car in gear to start it? ( Be sure emergency brake is set,tires scotched) Want to see if the neutral safety switch is good.

1 people found this helpful.
90

I did the procedure to relearn the gas pedal, it did not help. I can put it in gear and fire it with starting fluid. It only fires for a second or two and the wheels didn't move. I have it up on a lift. When I was putting it in gear I noticed that it doesn't have any feedback in the lever. I can't feel the resistance when it goes front reverse to drive. It's smooth all the way through. I looked at the linkage on the transmission and it appears to be intact.

2 people found this helpful.
90

I got a fuel injector tester that sends electronic pulses to the injector. I turned the key on to build up fuel pressure, then turned it back off and ran the tester on continuous mode for about 10 seconds. The fuel pressure did not drop or move when I tested any of the injectors. Is it possible that all 8 of my injectors clogged? It has been sitting for several years without running. The gas I drained out of the tank and fuel lines smelled old but it wasn't gummy at all.

1 people found this helpful.
90

It was my injectors. All 8 were bad. I guess they don't like sitting for a long time. I got a new injector, plugged it into the fuel rail and ran the tester on it and it sprayed gas out just fine. My volt meter still doesn't show any power going to it, I guess the pulses are too quick for it to pick up.

1 people found this helpful.

Your Answer:

1500

Looking for a Used 1500 in your area?

CarGurus has 22,590 nationwide 1500 listings starting at $3,300.

Postal Code:

CarGurus Experts

  • #1
    dandyoun
    Reputation
    2,370
  • #2
    Bobbie Burns
    Reputation
    2,300
  • #3
    GuruZD4Z6
    Reputation
    1,580
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Ford F-150
343 Great Deals out of 12,723 listings starting at $599
Used Chevrolet Silverado 1500
213 Great Deals out of 9,034 listings starting at $2,900
Used GMC Sierra 1500
188 Great Deals out of 8,956 listings starting at $1,000
Used RAM 2500
65 Great Deals out of 2,517 listings starting at $15,878
Used Toyota Tundra
33 Great Deals out of 988 listings starting at $9,240
Used Toyota Tacoma
43 Great Deals out of 682 listings starting at $9,975
Used Dodge Charger
31 Great Deals out of 972 listings starting at $4,888
Used Dodge Challenger
28 Great Deals out of 887 listings starting at $1,001
Used Jeep Grand Cherokee
110 Great Deals out of 3,487 listings starting at $4,950
Used Ford F-250 Super Duty
34 Great Deals out of 719 listings starting at $4,290
Used Dodge Durango
70 Great Deals out of 1,993 listings starting at $7,999
Used Jeep Wrangler
136 Great Deals out of 5,920 listings starting at $8,995
Used Chevrolet Silverado 2500HD
34 Great Deals out of 1,782 listings starting at $1,000
Used Nissan Titan
30 Great Deals out of 207 listings starting at $4,250

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.