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  #1  
Old 03-20-2012, 09:22 AM
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Help 98 R/T won't run.

Hello,

I have a 98 Club Cab R/T. It used to be a daily driver, but it's been more or less sidelined for the last 5 years or so. It was once again up to a weekly driver this year.

Last week I had it out, and on the way home, it quit at a stop sign, when I was pulling off. It fired up once or twice more, but would quit again when it was in gear and I gave it some gas. It was towed home. It acted fine before that, temperature and voltage were fine.

It hasn't run since. It might hit every once in a while, but not enough in a row to actually run.

I had thought that it might be a fuel issue. It's down to a quarter tank, and that's been in there for some time. I sprayed some starting fluid into the throttle body, and turned it over, with no change. Didn't hit any more often than without the fluid.

I pulled off the coil wire, and used a screwdriver to allow it to jump to the block. Plenty of spark there. That part was kind of cool to watch.

I pulled off the distributor cab; it looked ok on the inside. There was the white film from where it arced sometimes, but that could be a holdover from when I had a Mallory Ignition on there. There didn't seem to be excessive buildup on the terminals inside the cap.

I checked the spark plugs. I have Autolite 3923's in there, they've been there for a while now. Those have the screw on terminals. I don't know what that's good for. Three of those terminals came off when I pulled the wires off. The terminal hadn't been tight against the plug, and the threads up there had vibrated and had worn through. I was able to pull out those terminals from the wires, and replaced all four plugs on that side. No change in behavior of the truck.

There isn't a check engine light. I'll go today or so to see if I can pull any codes via the odometer screen.

What else can I check? This isn't my current daily driver, so there's no huge rush.

The only modifications that I still have on there are the Autolite 3923 plugs, aftermarket cap and wires, MP computer, cold air tube, maybe one or two other small things. There's about 120k miles on it.

Thank you for any help.

James
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Old 03-20-2012, 09:42 AM
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It sounds like the fuel pump. My '97 Ram did the same thing when the pump was dying. Check the fuel pressure at the rail. It could also be that sitting 5 years, the fuel is stale and contaminated with rust and moisture.

BTW, I have always heard never to use starting fluid in a FI engine.
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Old 03-20-2012, 12:18 PM
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I'll check it at the fuel rail.

During the 5 years, it did intermittent stints as a weekly driver. Though on at least two occasions, it sat for around a year each, with water pump woes or brake woes.

James
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Old 03-21-2012, 02:44 PM
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With the key in the ON position, I got a healthy squirt out of the test port on the fuel rail.

There is no Check Engine light, and no codes came up when I checked for them. Is it possible for there to be codes in which a scanner would reveal, but not the Self Check?

I also checked the resistances of the Crank Position Sensor, which seemed to be normal (infinity/3.8Mohm). I got this out of my Chilton Manual.

It hit a few more times than before when I attempted to start it today.

James
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Old 03-21-2012, 03:27 PM
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A healthy squirt isn't a good indicator. You need a pressure gauge to test what the actual pressure is.

(Downloaded from the web)

"Anything above 40 pounds (cranking) will run it ,but to run it right you need at least 45 pounds on it. Specs are about 55-58 pounds on a new pump,once they get broken in though the pressure drops to about 55 pounds,and normally stays at that point if the regulator is working right on it."
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Old 03-22-2012, 07:53 PM
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You said there is spark from the coil but didn't say if you checked for spark at the plugs. Is there spark at the plugs?
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Old 04-07-2012, 11:00 PM
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Try temporarily replacing the coil to distributor wire with an old spark plug wire. If it cranks you need at least a new coil wire.

It sounds like it could be fuel pressure to me tho.

Although MOST fuel pumps either run or dont. My 1992 dakota gradually lost fuel pressure to the point that it would run but had no power.. Sneaked up on me very gradually. But it would still idle just fine. A new pump and 5 hours of work Fixed It.

I have a personal saying that " If you think its fuel, its electric and vice versa".

earl
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Old 12-01-2012, 04:12 PM
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I finally took another look at this truck again today. I borrowed a fuel pressure tester from Autozone, according to it, when the engine was turning over, I had 46-48 lbs of fuel pressure (at the fuel rail).

So then I decided to bite the bullet, and on blind faith, order a new camshaft position sensor. Autozone and Advance both report that they don't show a cmps for this year of truck.

My Chilton manual did mention one, but I suppose it could have been referring to all the other trucks it covers. I'll look at it again, though.

With a new battery (the old one died over the summer), it did catch once or twice, probably just one cylinder hitting each time.

Any other thoughts?

Thank you for your help,

James
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Old 12-01-2012, 08:30 PM
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Cycle the key three times from off to on leaving it in the on position the third time. What code does it read out on the odometer? you may have to try this several times but it will read a code out or say Pdone.
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Old 12-02-2012, 01:46 PM
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I read that, and I thought "Why didn't I think of that?"

So I went out and tried it. I had to hold in the odometer button when I cycled it.

It said CHEC, then went through and each of the LED blinked one at a time, then it read all 8's. Then all the other lights and meters of the instrument cluster were tested.

I didn't get any codes, or Pdone.

So then I figured that all of them might have been forgotten, since it went so long with a dead battery. So I sat there and tried to start it several times. Again, it would hit occasionally, but never twice in a row.

Then I went through the on-off cycle again, to check it after that. Still nothing.

I went out to borrow a diagnostic tool from the parts stores, but they don't loan those. I'll do some more thinking on it.

Thank you,

James
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Old 12-02-2012, 08:10 PM
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You can't hold the odometer button, that causes the instrument cluster to do a self test.

I know they can be a pain to get to read the codes out, but it will do it.

Anyways, do you have spark at the coil? Coils were pretty common for going bad. You should be able to put a noid light in the connector for the coil and have someone crank it over to check that the computer is controlling the coil properly.
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Old 12-06-2012, 05:14 PM
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I tried the cycling the key a few more times, still nothing. Next week, I'll figure out how to have someone loan me a scan tool to check it with.

I do have spark at the coil, but haven't been able to check at the individual plugs.

I still think that it's some kind of sensor being bad, and not allowing each plug to fire. But I don't know any more than that.

Thanks,

James
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Old 12-06-2012, 05:38 PM
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Quote:
Originally Posted by inflammable View Post
I tried the cycling the key a few more times, still nothing. Next week, I'll figure out how to have someone loan me a scan tool to check it with.

I do have spark at the coil, but haven't been able to check at the individual plugs.

I still think that it's some kind of sensor being bad, and not allowing each plug to fire. But I don't know any more than that.

Thanks,

James
Whoa, hold up there friend! Your line of thought is all out of whack. There is no sensor to fire each plug, the distributor sends the spark to each plug at the proper intervals.

The big wire from the coil to the distributor cap carries the spark from the coil to the distributor cap, as the rotor turns inside the distributor cap it distributes the spark to the proper plug at the proper time assuming that the timing and firing order is correct.

No offense intended but if you don't understand how this works you need to find someone near you who does and will help you get this thing going.

Good luck to you.
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Old 12-06-2012, 11:48 PM
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Well like said. The distributor distributes the spark to the cylinders. So check for spark at the plug. And it should be a good fat spark that jumps a 3/4 inch gap. If you have spark at the end of the plug wire then I'd be checking your spark plugs.

You have fuel pressure and spark at the coil so you know the computer is getting signal from the crank sensor. The only other thing to check after the spark plugs is to see if the injectors are being fired using a noid light.

I had a 2002 Dakota come in the other day and snapped this photo for you. I cycled the key really fast. I did try it on a 2005 Durango today and it didn't work. But that's a completely different vehicle.
Attached Images
File Type: jpg Photo523.jpg (31.9 KB, 7 views)
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  #15  
Old 12-07-2012, 08:47 AM
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Yes, thank you, I do understand the basics of the electricity going through the coil and distributor to the spark plugs.

If you don't mind reading the previous posts in this thread, I've already checked the spark at the coil. Later, I sprayed starting fluid into the intake, and the engine still didn't catch. More recently, I checked the fuel pressure at the rail, while I was cranking it, and still nothing.

By two of those indications, this doesn't seem to be a fuel problem. There's a chance it's the individual fuel injectors, but still, something should have happened when I sprayed starting fluid to it, if it's a fuel problem.

The spark at the coil is a good sign, but like what's been said, I need to check each spark plug. With this being a computer controlled vehicle, the computer may be fouling things up. I ran a test of the Crank Positioning Sensor, as mentioned in a repair manual, and that seemed to be satisfactory. That same manual mentioned having a Camshaft Positioning Sensor, yet two of the Parts Stores around here suggested that I don't have one. I'll have to do some more investigating.

I've looked inside the distributor cap, but didn't see anything out of place.

Thank you for the photo. I want to say that at one point I was able to get codes out of the truck using that method, but it would have been too long ago to remember any tips to it.

Thanks,

James
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Old 12-07-2012, 06:38 PM
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I have read this thread from the beginning, in fact in reply number 6 I asked if you had checked for spark at the plugs.

If you have spark from the coil the computer and crank position sensor are doing their jobs, the computer has nothing to do with sending the spark from the distributor to the plugs, it just fires the coil, the rotor button and distributor cap does the rest.

Check for spark at the plugs before you do anything else. If there is no spark ask about that.
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Old 12-07-2012, 10:28 PM
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When you say you have spark, just how big of a gap will that spark jump?
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Old 12-11-2012, 09:14 AM
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I had a fellow from a nearby repair shop come out with a DRB scanner. He reported that there are no codes in it.

Similarly to you all's suggestions, he too suggested to check the spark at each plug, and also suggested that it may have jumped timing.

The temperature is in the 30s right now, wet and overcast. I think I'll wait for a prettier day for that.

Thank you,

James
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Old 12-11-2012, 03:41 PM
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Timing chain.

But first, do you have a timing light? I know these newfangled engines don't have timing marks but a timing light is a pretty good tool just to see if you have spark at the plugs.

If you could fashion some sort of way to indicate TDC on the damper, you could also see if the timing is "close".

I once had a car with a worn out timing chain that acted just like your truck does right now. Crank, crank, crank, sputter a little now and then, crank some more, but wouldn't run. Just something to consider.
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Old 12-11-2012, 03:46 PM
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Quote:
Originally Posted by inflammable View Post
. . .My Chilton manual did mention one, but I suppose it could have been referring to all the other trucks it covers. I'll look at it again, though.
. . .
And if you want to get a serious book with which to do work on your truck, dump the Chilton/Haynes crap and get one from the factory. You won't regret it.
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Old 12-11-2012, 09:08 PM
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And if you want to get a serious book with which to do work on your truck, dump the Chilton/Haynes crap and get one from the factory. You won't regret it.
I'll second that. Those manuals aren't worth the paper they're printed on.
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Old 12-11-2012, 09:49 PM
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Hopefully, if I can get this thing to run for a little while, then I can get it sold. The Chilton manual will go into the backseat with some parts that I never put on.

I do plan to put a timing light to it, before I pull off everything on the front of the motor. I expect I can find TDC by manually rotating the crank, and keeping an eye on the spark plug hole. Then, just have to guess if it's the compression stroke or exhaust stroke. Could do that by pulling off the valve cover, and watching the rockers.

Boy it sounds like a lot of work.

Thanks,

James
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Old 12-12-2012, 10:00 AM
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Actually, it's very easy to find TDC on #1. Take out #1` plug and put a finger at the hole. Turn the engine manually until you feel pressure out the plug hole. Then it's on the compression stroke. If you have a timing indicator, when it comes to TDC, that's it. But the very first thing should be, now you know you have spark and fuel, is to check compression. The three basics are spark, fuel, and compression. Has to have all three to run. So pull all the plugs and check compression. Should be fairly even on all.
You have spark from coil to distributor cap. Could be a cracked cap. Sometimes very hard to eyeball. Plug wires might be worn out and leaking.
Could be a cold starting problem. Might want to check things related to cold starting, such as mass air flow sensor (terminology might be different).
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Old 01-26-2013, 07:23 PM
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I've been having the same problem but with a 1997 Dakota with a 3.9. It has 48lbs of pressure at the fuel rail, pulled a plug wire and hooked a sparkplug and grounded it, has spark at plugs. replaced Crankpostion sensor and still nothing. when engine is turning i had a testing connected to fuel injector and it lite up while engine was cranking. it is also very cold here, todat it got to 26 degrees. does ,make me think maybe it is the mass airflow sensor which i think is on the back of the TBI. the battery has 13.5 volts so it's ok. hadn't thought of the timing chain because i,ve seen these engines go over 300k on the factory chain, but i'll check that tomorrow. i was wondering if Inflammable ever got his truck figured out. I've never seen a set of sparkplugs kill and engine that was running fine. maybe hard starting and loss of power. but never seen them kill a good running engine.
Thanks
Dave.
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Old 01-27-2013, 10:40 AM
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Check injector ground.
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Old 01-27-2013, 09:13 PM
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Okay, here's the skinny on how i got it running. i put a new battery in it and it didn't make that much different. reason i did the battery is that it was 12 years old and going bad. but after replacing it it would try to fire though. i checked number one plug and it was soaked with gas ???? so i did the old crank the engine over while keeping my foot on the throttle and moving the throttle blades. after about a minute of continuous cranking and fancy footing the throttle, it fired off finally and ran !!!!!!!!!! it wouldn't idle for agood thirty minutes so i took it for a drive thinking the computer needs to relearn the throttle postion sensor. after a three mile drive it was fine. now i just bought this truck and it had trouble idling until it got warm. my brother is a great technican and after telling him everything that happened he said it's the engine temp sensor for the computer. when it's cold it floods the plugs but are fine when warm . I've seen that before myself but forgot about it. he deals with it on a daily basis, i only see it every couple of years when i pick up a turd to fix. So tomorrow i'll replace it if after i try starting it and it does the same thing again.
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Old 01-28-2013, 09:12 AM
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Hmmm, engine temperature sensor.

I'll give it a look if nothing else works. I haven't worked on the motor lately. I had the truck across the street from my home for much of last year. It was parked by the curb. On New Year's Day, I came outside to find all the tires flat. It turned out that there is an occasional vandal in my neighborhood. Several people had stories of finding flat tires. No rhyme or reason to it.

Well, I put it up on blocks, and put the wheels inside the garage. It wasn't much of a plan, but I didn't want to spend money on new tires if I couldn't get the truck to run. Shortly after, the City took exception to my truck on blocks, so I had to go out and get a set of used tires for it, and get it pulled to around the back. That aggravation took some out the rest of the fun that I was planning on having by troubleshooting the motor.

I found in my Chilton manual a way to test the Cam Positioning Sensor while the truck is cranking, so one of these days, I'll re-test all the plugs for spark, check the timing, and verify the cam sensor is working. If all of that proves to work, then I'll have to make a new plan.

James
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Old 01-29-2013, 01:05 PM
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TADAAAAAA!!!!! Fixed!!!! i miss quoted the sensor. Coolant temp sensor. it's to the right of the thermostat . small sensor that takes a 1/2 inch deep well socket to get at. it's a two wire sensor. truck runs like it should now. yours is probably flooded like mine was so you'll either have to remove the plugs and spin it over to get rid of the fuel and maybe put new plugs in it. the sensor was only $16. i'd put that in first before you try starting it and before you pull plugs to get rid of extra fuel. good luck !!!!
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Old 02-11-2013, 12:07 AM
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Hve any luck Inflammable????
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Old 07-10-2013, 09:41 PM
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It's running now. I don't know exactly what it was, but this is what I remember doing.

I know that I bought a new battery for it either in late fall or early winter. I think I tried it out with the new battery, with no luck. I only say that, because I do remember putting on the battery charger for a day afterward. The previous battery died because I left connected. It wouldn't take a charge, either, but it was 5 or 6 years old.

More recently, I went out and took off the distributor cap, rotor, and distributor pickup (cam positioning sensor). Just to look at them, I guess, as I put them back on. I was thinking to replace the distributor pickup and trying it out.

Then, two Sunday's ago, on a whim, I put the battery back into, and it started right up!

Old gas, whatever else, it caught on the first try! I let it run for a while, then had to turn it off, as it was getting too hot. I'd pulled the fan and shroud off of it, in preparation to check the timing and whatever else.

With the fan and shroud back on, it started up again, and I drove it around the neighborhood.

I ordered a new distributor cap, rotor, and distributor pickup from Parts Geek, and put them on tonight. I drove it across town, and plan to go back to driving it to work one day a week.

All I can figure is that between the cap and rotor, something got fouled up. While it was running. Then pulling them off, and putting them back on straightened out everything.

I decided that the distributor parts would be the point when I'd start trusting it away from the house. Not in a rush to pay $60 to get it towed home again.

James
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