I am looking at a set of 8 5.2 and 5.9 injectors on line for only $ 53.00 / I gess it says 1996 - 1999 / what DO 4 hole injectors MEANING AND what are the other style injectors. whitch ones are best, ANY ONE HERE KNOW, AND they come with new plug for wires setting on top the injector plug in.
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If the issue had just now showed up I actually would have guessed it was the air flaps being left shut. But apparently Ron started having the issue.
I do wonder if itās the fuel system itself going out, like maybe the fuel pump or a leak in the system. The only other clue is that apparently in the winter it will run okay until itās fully up to temp, but in the summer it just runs rough all the time.
Thatās what makes me think itās the Intake Air Temp sensor. Maybe it could be another temp sensor that runs to the ECM.
If it ran bad on woodgas as well as gasoline it would make me think it had a bad ignition coil or some spark plug wires getting too hot.
Iām also wondering if the wiring for the fuel pump shutoff is damaged. Maybe when the wiring is warmed up itās gaining some resistance or shorting out, and the warm ambient temps are just enough to have it run crappy.
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Air or coolant sensor is my bet, Cody. Unless the ECM is bad. That was the case with my Mazda truck.
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I know he had the issue. What I donāt recall with 100% certainty is if he had the issue prior to converting to woodgas. I think that conversation goes back to possibly the yahoo lists and all those archives are gone. But I THINK that is why he used it as the donor vehicle in the first place, but I would only put about 50% certainty on my recollection.
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MAYBE if he scanned for codes or live data, he might get a clue,if he caught it when it just starts running rough. I havent used my $ 200 scan tool in years, it was good up to 2003- when i was in mechanic school.
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Kevin this is the truck that Iām getting, Ron Holmack passed away. If I had the truck in front of me Iād definitely scan the live data if thatās possible on an OBD1 truck.
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Scanning very possible.
Just not so easy anymore. As a pre-OBDII it does have a special Chrysler/Dodge/Jeep unique diagnostic harness plug. This era different for GM; Ford and all others. Different communications languages codes too.
Like Kevin I still do have one of these for most all pre-1996 scanners: adapter plugs and adapter keys.
Look up current available on-line and you see the much higher prices to buy a go-back scanner kit.
Cody what you do not scan (had no fuel pressure sensor) for is system base fuel pressure. This is adapted-in Teed gauge read.
This old system and most back then did have engine vacuum driven on the engine fuel rail fuel pressure regulators. That has to be checked visually; vacuum line on and off and then hand vacuum pumped too.
Far too, too many possibilities to just throw parts at this problem.
Affordable aftermarket parts too often are shit quality and grow more problems when you try and shotgun anymore.
Just smelling the exhaust when it goes hot running bad can point out if it is going too lean; or too rich. Subjective. Takes experience.
S.U.
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Iām familiar with the classic pitfall of firing the Parts Cannon at a Pre OBD2 vehicle. Luckily I helped my friend prevent doing so with his 1989 Chrysler Renix Computed Jeep Cherokee by figuring out his crappy running was due to a malfunctioning EGR. Disconnected EGR vacuum line and the Chrysler/Jeep 4.0 started running just fine.
Thereās a nightmare zone for me, anything Computerized with a Vacuum Spaghetti Nightmare of sensors and solenoids 1985-1996.
All I know from what Adrianne has told me is it āsounds like itās choking for air when itās warmed up or warm outsideā. Iāve been thinking of having her ask for a mechanic to do some basic diagnostics like test the fuel pressure at the rails. Maybe a good old sniff test. Check voltages and resistances. I texted her just now to ask her son-in-law for an opinion.
Vacuum fuel pressure regulator sounds like another very good probability.
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apparently the 5.2s have a āweak headā. But they also have some other issues like gaskets around the intake among other things. I would look up all the TSBs from Ram to see what they mention as issues. But could a leaking head or gasket cause the issue?
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Yes. A leaking under intake floor plate can cause exactly these symptoms.
The intake is an aluminum casting. The stamped steel floor plate is cover over the open bottom where the casting cores were removed.
Aluminum and steel heat expand at different rates. The gasket between these from hot oil splash; hardens, cracks and will even chunk out.
Warmed up then allow air-vapor gasses from the crankcase get sucked up into the intake stream upsetting the intended mixing ratio.
The in-shop quick diagnosis for this was to shine a flashlight down the propped open throttle plates. Seen pooled engine oil . . . the plate is leaking.
And that explained the customers complaint of intermittent weird idling. Too-lean, too long codes and PID values in the computers memory.
Quote the customer for an R&R of the intake for floor plate gasket replacement.
Quote for distributor cap and rotor replacement. Maybe even speak plug wires replacement since then it will be easy and almost labor inclusive.
By the way I had the exact same cold versus hot running, idling problems on the Wifeās old Oldsmobile Delta 88 full sized car. Cast iron V-8 with a cast iron intake manifold. Heat induced intermittent sucking false air internally or externally. Drove me nuts finding it thinking it had to be the base of the quadrajet carburetor. Or a feed back control problem.
S.U.
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my auto exray EZ scan 5000 i bought back around 2003- it had live data somewhat, you could see 6 or 8 i think, though i caint remember how many-voltages,amps,resistance,vacuem type stuff- it allso had freeze frame that could catch a bug while it happened- i never used that part of it though,so i would have to go back to studyās on that part of its claim- YOU will likely find the problem obvius likeley, with your experiance. THE intake and head gasket is a very likely probable cause, could be seeping just enough to cause the simptomās, if i had it with all these type problems,that would be my nearly first eliminator rocket. I should probley through a set of gaskets on my old 1999 5.2 dakota, its got around 180.000 miles on it.
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