Forums
Forum Tools
|
 |
01:19:43 - 12/20/2024
V8 Dakotas
| From | Message |
At Wits End
Dodge Dakota
JOIN HERE
6/08/2011
13:37:14
|
 Subject: Ready to push off a cliff
IP: Logged
Message:
Good morning Gurus. You guys have helped me with all of my issues in the past, but this one has me stumped beyond understanding.
Got a 98 Dak, 318, 4x4, auto trans that I can not get to stay running. Here is the back story:
First, the beast ran like a champ for 13 years with no major issues, then I go and break my leg and the truck starts to not want to start at intermittent times. First time, had a friend borrow it, drive it all day, then comes to get me from work, I get in crank it up, and it wont fire. try and try and try and nothing. Started to wear out the batt. so I just had it towed to my house. Checked it out and was not getting fuel at the rail. Figured, since it was a poor few months and I threw 5-15$ in gas at a time, I probably burned out the fuel pump, as it has never been changed and I am at 197,xxx miles. Get it towed to Good year, and they confirm the pump, change it, and it runs. I go to pick it up, in the cold, and it will not start. they take it in the shop (where it is warm) and the next day they tell me it works, come get it. I go in, fire it up, and the idle is very low, had to keep pumping the pedal to keep it up. Tell GY it is not alright, and they keep checking. Next day they say they cleaned out the IAC and it is ready. Good...pick it up, and it is running nicely. Two days later, I am out and about, run into a shop for ten min, come back out and it starts, but when I put it in gear, it dies. Screwy. A friend says crank shaft position sensor, swap it out, no go. Will not fire at all, but will crank and crank. Tow it to my house.
Think about what could be going on, and realize it is below 35degrees everywhere it will not run (at Good year, it was running great, IN the shop, outside when I would go to pick it up, nothing) So I confirm this by trying at 35 or below, no go, wait until it warms up outside, and it starts right up. Stalls again in another parking lot after a week of driving by looking ahead at the weather to make sure it will be warmer(I know, I know...but it is my only car) and after a week, it is nice out and then leaves me stranded again at 60degrees out side. 3rd tow home.
It sits at my house while I try and figure it out. While going through things (TPS, MAP, IAC, fuses, etc.) I unplug the PCM and plug all connectors back in, try it and it starts like a champ. Figure that is the issue, and resetting it fixed the issue, so I go with that, and order a new PCM. Get the computer in and plug her in and no go. Puzzled, I start changing sensors. Flip the TPS, and she fires right up! Drive for four days, and half way home AGAIN, it sputters out like it is out of gas, then kicks back on a few times, i drive while praying to get me home, and 5 miles out, it dies and wont start again. I go to pull TPS connection off, and the TPS breaks apart in my hand. I pull the MAP vac and sensor off, TPS connection off, and it starts enough to limp home, reving up and down and up and down (from no MAP plugged in)the whole way home. Assume it was the TPS, since it ran for four days after I replaced, so I got a replacement for the broken one and put it on and now it is doing the same thing again, cranks, sometimes fires, but will not idle. Ok, so that is where I am at...
I can get it to stay idleing, if my buddy ever so slightly opens throttle plate when I crank. I have replaced the TPS again, MAP and IAC sensors. IAC screams when I try to fire as well, like it is not getting enough gas. Last night, i hooked up a fuel pressure gauge at the rail, and it read nothing, thought it was not hooked up right, then I tweaked it, and tried to start it, and it jumped to 10psi. So, I am at a loss, and ready to just call the junk yard and give her away. Any ideas or questions from you wizards would be most appreciated...
*NOTE* I got it to idle smooth one time by removing all of the fuses (20s) in the under the hood fuse box...then plugged them in one by one and when I got to the O2 sensor fuse, (last one) it died. Also, giving it gas causes a backfire or causes it to die immediately. when I had it idling smooth with out the O2 sensor, i pushed the brake and it died...
Thanks Guys!!
What is causing no/low fuel pressure?!
|
David R
Dodge Dakota
JOIN HERE
6/11/2011
21:48:29
|  RE: Ready to push off a cliff
IP: Logged
Message:
Im not much of a mechanic but id definately have to say its the PCM. Even though you replaced it there is the slight chance that the new one is failed. I was having similar problems with my 95 dakota and the PCM fixed it for the most part. Also somebody on this forum told me to check a three way splice on the drivers side wheel well connecting to the relay box. Im not sure if its the same for a 98 but its worth checking out. If the splice is corroded then that is more than likely the problem as it sends power to the PCM and the fuel pump.
|
daddio
Dodge Dakota
JOIN HERE
6/12/2011
08:51:55
| RE: Ready to push off a cliff
IP: Logged
Message:
"What is causing no/low fuel pressure?!"
Bad Fuel Pump or pressure regulator. Have you tried checking for codes?
|
ES
Dodge Dakota
JOIN HERE
6/12/2011
14:16:04
| RE: Ready to push off a cliff
IP: Logged
Message:
Not sure if it applies to how the dakotas function but i know in jeeps that if the timing chain gets excessively loose it will cause no starts to excessive cranking cause of how the pickup in the distributor is seen vs crank position. It also sounds almost exactly the way the pickup in a jeep inside the distributor will fail. Though in this case you would have fuel but no spark.
If i were you id look into the relay for the fuel pump it might need to be replaced. If i recall some of the relays are the same and to trouble shoot just swap a relay from another and if the fuel pressure comes back you found the culprit. Also from experience the cheapy iac motors from the autoparts stores dont seem to last. Ive been through 2 of them before going back to a genuine part cause they would fail within a year and cause a no idle situation especially when it was cold outside.
Outside of this id look into faulty or dirty connections.
|
Marty
Dodge Dakota
JOIN HERE
6/21/2011
21:01:31
| RE: Ready to push off a cliff
IP: Logged
Message:
My '99 Dak 4x4 V8 can be tempermental in the cooler weather too,like when its 40 or below.
|
At Wits End
Dodge Dakota
JOIN HERE
6/22/2011
18:24:12
| RE: Ready to push off a cliff
IP: Logged
Message:
The one thing that is killing me is that when I remove this O2 sensor, it will start. It runs rough, revs up and down, which to mee seems to be the MAP, but the wiring could have to do with it...does anyone know about this splice? I found one about 6" from the PDC that split to auto shutdown and one of the 40A fuses, but that is not it, because I re-spliced that one. It is like there is another connection in the circuit when the O2 fuse (20a) is connected.?
I did test all relays.
|
ES
Dodge Dakota
JOIN HERE
6/29/2011
02:28:47
| RE: Ready to push off a cliff
IP: Logged
Message:
That is a weird one but yeah with no o2 sensor it will run like that. I had a rabbit eat through the wires on mine once. It will even stall at that point.
Id almost wonder if a wire is grounding out somewhere or you have a bad chasis ground. Cause if you unplugged the o2 sensor and it fired id be suspiciouse of some feed back usually related to poor ground some where or wires that have become bare and rubbed against each other. If i recall the grounds are to the engine then if memory serves me well one is on a exhaust manifold bolt another on the chases then frame and firewall.
If it started happening shortly after a pcm swap id question if the new pcm was properly flashed with the correct vin and if maybe one of the pins on either the pcm or plug have become loose bent or corroded.
TBH it has me stumped so im just tossing stuff out there now that sort of sounds like something that may be happening.
Best of luck ive been there with electrical and sometimes the weirdest crap causes an issue that even when fixed still boggles the mind how it could have been the problem.
|
| | P 1 |
|
Post a reply to this message:
Username Registration: Optional
All visitors are allowed to post messages
|
|
