Need Help

[Scooterwrench]

Sounds like you may have some electrical gremlins. Start with the grounds and make sure they have a nice clean connection. The EGR control valves ground is up there on the thermostat housing as well as the PCM ground. Engine to body ground strap, body to frame ground strap and the ground over there by the battery. Give your battery terminals a good cleaning. Then if you still have issues put some sort of scanner on it before throwing more parts at it.

 

[gladescot]

As mentioned already, our troubleshooting relies on working parts and all systems hooked up as they should be. You had mentioned the plugs and the wires being replaced in your first posting. Looking at the photos of your plug wires, they do not look new to me. You also identified a bad spot on one of them in one of your recent comments and have taken the picture of it. The picture of the wire is what leads me to believe the wires are not new.

Additionally, disconnecting components when we are working on an integral system (fuel delivery) for proper engine operation does not aid in the troubleshooting steps. It complicates them.

In this case, the majority of us believe the fuel delivery system is what needs to be concentrated on first. Make absolutely sure it is delivering the required fuel pressure to the TBI before doing anything else. If we find it is working fine, we will move on.

In the meantime, while you are waiting for the tank level to drop down, take the time to ensure the complete integrity of the vacuum lines attached to the TBI components AND also check the one going to the brake booster, which is an often overlooked part of the vacuum line system.

The tank level has dropped to less than a quarter tank. I did another fuel pressure test and got 10 PSI at all RPMs again.

 

[H2814D]

The tank level has dropped to less than a quarter tank. I did another fuel pressure test and got 10 PSI at all RPMs again.

OK. If we are going to rely on the fuel pressure gauge as being accurate, then we can discount the fuel pump as being the problem. My concern, though, is if it is original equipment, as you mentioned earlier, I would find it hard to believe the connecting hose is still in good shape, but that's just me.

I just went back through all of the comments posted here and noticed you provided your "live data" in one of them. ALL of the EGR data showed zeros. I don't believe we should be seeing that. I would expect there would be some numbers there that would indicate a properly operating EGR Solenoid. I believe I did see where you replaced that component though. So I want you to go back to it and ensure all of the vacuum lines and wiring that go to and from it are all connected and in good shape. What brand of Solenoid did you replace the original one with?

One other thing. As Scooterwrench mentioned, check your electrical wires. On your truck there is a wire connection mounted on the firewall in front of the passenger side. It may or may not still be enclosed behind a plastic cover. If it is, remove that cover and look at it. There will be several connection points that supply power to various components and the computer in there. Before messing with it, remove the negative battery cable. After you have done that, remove each wire and clean the connection and then replace each one, one by one. Then put the cover back on. After you have done that, reconnect the negative battery cable.
Let us know.

 

[Scooterwrench]

I just went back through all of the comments posted here and noticed you provided your "live data" in one of them. ALL of the EGR data showed zeros. I don't believe we should be seeing that. I would expect there would be some numbers there that would indicate a properly operating EGR Solenoid.

There should be no EGR in the idle state. Any EGR opening at idle will make it idle poorly or not al all.

 

[gladescot]

There should be no EGR in the idle state. Any EGR opening at idle will make it idle poorly or not al all.

I believe you are correct, the EGR did not engage until about 900-1000rpm. I manually actuated the EGR valve with a vacuum pump at idle to ensure the EGR valve was working per the emissions and drivability manual and it stumbled and idled poorly as it was supposed to at that rpm. At the 900-1000 rpm range I can see the EGR usage increase as it engages on live data.

 

[gladescot]

As far as my other problems go, I no longer have the low power and shaking issue I used to have, it appears that the spark plugs fixed that. Now I only have the "Chuggle" when coming off idle up hill (This does not happen if I unhook the EGR vacuum so I believe it is related to the EGR system) and a "hunting for idle" issue on cold start (This happens regardless of whether or not the EGR vacuum is installed).
As far as EGR solenoids go I replaced it with a Duralast Brand part as it was what I could get the quickest and cheapest as I work in the parts department at a Chrysler dealer so I was able to get it delivered to my work with our affiliate account with AutoZone.

 

[gladescot]

OK. If we are going to rely on the fuel pressure gauge as being accurate, then we can discount the fuel pump as being the problem. My concern, though, is if it is original equipment, as you mentioned earlier, I would find it hard to believe the connecting hose is still in good shape, but that's just me.

I just went back through all of the comments posted here and noticed you provided your "live data" in one of them. ALL of the EGR data showed zeros. I don't believe we should be seeing that. I would expect there would be some numbers there that would indicate a properly operating EGR Solenoid. I believe I did see where you replaced that component though. So I want you to go back to it and ensure all of the vacuum lines and wiring that go to and from it are all connected and in good shape. What brand of Solenoid did you replace the original one with?

One other thing. As Scooterwrench mentioned, check your electrical wires. On your truck there is a wire connection mounted on the firewall in front of the passenger side. It may or may not still be enclosed behind a plastic cover. If it is, remove that cover and look at it. There will be several connection points that supply power to various components and the computer in there. Before messing with it, remove the negative battery cable. After you have done that, remove each wire and clean the connection and then replace each one, one by one. Then put the cover back on. After you have done that, reconnect the negative battery cable.
Let us know.

I have already repaired my PCM ground on my intake manifold previously. Just to be sure I double checked the resistance from the battery and it was not high at all. As far as the power supply side of things I have never taken that cover off mine so I will be doing that tonight after work and cleaning up the connections.

 

[gladescot]

OK. If we are going to rely on the fuel pressure gauge as being accurate, then we can discount the fuel pump as being the problem. My concern, though, is if it is original equipment, as you mentioned earlier, I would find it hard to believe the connecting hose is still in good shape, but that's just me.

I just went back through all of the comments posted here and noticed you provided your "live data" in one of them. ALL of the EGR data showed zeros. I don't believe we should be seeing that. I would expect there would be some numbers there that would indicate a properly operating EGR Solenoid. I believe I did see where you replaced that component though. So I want you to go back to it and ensure all of the vacuum lines and wiring that go to and from it are all connected and in good shape. What brand of Solenoid did you replace the original one with?

One other thing. As Scooterwrench mentioned, check your electrical wires. On your truck there is a wire connection mounted on the firewall in front of the passenger side. It may or may not still be enclosed behind a plastic cover. If it is, remove that cover and look at it. There will be several connection points that supply power to various components and the computer in there. Before messing with it, remove the negative battery cable. After you have done that, remove each wire and clean the connection and then replace each one, one by one. Then put the cover back on. After you have done that, reconnect the negative battery cable.
Let us know.

I just cleaned the connections behind that cover and replaced the plug wires. I'm still having the "chuggle" at 1000 rpm uphill with the EGR connected and it still does not do it with the EGR vacuum disconnected. The connections I cleaned also were not dirty at all, just a little sand from taking it through a dirt road a while ago.

 

[toolmakerson]

I just cleaned the connections behind that cover and replaced the plug wires. I'm still having the "chuggle" at 1000 rpm uphill with the EGR connected and it still does not do it with the EGR vacuum disconnected. The connections I cleaned also were not dirty at all, just a little sand from taking it through a dirt road a while ago.

Well, I replaced the EGR solenoid and it appears to have improved it a little bit (I didn't do it for nothing though, the EGR solenoid filter was completely gone so I needed it anyways). It still "chuggles" pretty bad up hill at 1k rpm to the point where it drops so low on rpm that the gauge can't read it and it almost stalls.

I'd find a country road and hook scanner up and look at data while this is happening. Gotta be some wacky fuel trim or somethin whacky while that's happening. I'd check it all, Engine 1, Engine 2, Sensors, etc.

 

[H2814D]

I just cleaned the connections behind that cover and replaced the plug wires. I'm still having the "chuggle" at 1000 rpm uphill with the EGR connected and it still does not do it with the EGR vacuum disconnected. The connections I cleaned also were not dirty at all, just a little sand from taking it through a dirt road a while ago.

If you are down to a properly running truck when the EGR system is disconnected from the computer interface, then we should be looking at why that is. The computer relies on proper data from the EGR system for closed loop operation. If you have replaced the EGR Valve with the proper one, then the other part of the equation should be the EGR Solenoid.

I just looked up the reviews for the Autozone recommended Duralast Solenoid you probably purchased and did not see anything glaring in the reviews, as far as quality issues, for the different models they sell. That does not mean that the part is good though.

I am assuming you have double checked all of the vacuum line routings to it and the wire connections. That solenoid does have two ports that are very similar to each other. One of them is simply a vent. The other port is for the vacuum line. I don't like replacing parts, or suggesting others do that, unless the part is known to be bad. In this case, however, I would take the chance and suggest the solenoid be replaced with a GM/ACDelco Part, just to be sure.

Just for the fun of it, though, I also looked up the Delphi EG10099 EGR valve you originally put in there, but I believe you have since replaced it. His symptoms seemed awfully close to yours. Anyway, for the Delphi EGR, this review popped up: "Its is an exact fit. Purchased New and installed. Immediately after installing first drive I had a hesitation from a stop and stalled. Truck idled rough and bounced around between different rpms. Truck stalled twice when stopping as RPM's were sporadic. Upon further online reviews of the DELPHI EGR 10099 there are multiple online reviews that describe this same scenario as having issues after installing the Delphi Egr. The truck had a "Check engine light" and was coding the number (32). I went with the AC DELCO 214-5073. After Replacing the Delphi EGR with the AC DELCO EGR my truck now functions 100% as it should with no hesitation or stalling. I am writing this review to hopefully save someone else some time from having to install 2 Egr valves. Go with the AC DELCO and NOT the Delphi 10099. I wanted to rate the Delphi EGR with zero stars but you have to pick 1 star to leave review. My customer service was excellent at both locations that I visited to get the parts."

At this point, an actual scanner is where we are at. I am still having a hard time believing the fuel pump connecting hose is still in good shape, though, because you mentioned it was original. Unless someone else has something other than what we have already mentioned, it would be difficult to provide any other useful information.