88 D100 issues

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The electronics are a huge pain in the *** when they fail.

So you never got back to me, did you pull the fuel filter and cut it open.

That TBI setup needs a good amount of fuel pressure too, would bet the in the take fuel pump is failing . . . low pressure.

Wonder where the fuel fiter is on that one, back at the tank like some of the newer cars ???

Pop a new fuel filter and try it again. Think that Dodge has a plastice gas tank, so that helps to prevent rust and sediment in the tank.
Water condensation in the tank though you need to change the fuel filter for that.

Good Luck.

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If you have ever done any body and paint work you know your spray gun does not give you a nice fine mist at low pressure.
Same with the throttle body injectors, they need good pressure to spray a good atominzed pattern. Low fuel pressure is just going to dribble the gas in there like you are pouring it in with a spoon.

One Old mechanic showed me a trick with a timing light to watch the spray patterns of the throttle body injectors when you rev it up to about 1500 rpms.
It pulses the light as you shine it on the working throttle body injectors. You will be able to see if they are spraying nice with this technique.

Hook the timing light up to the battery + and - , then the lead on to number one plug wire. Give it a go, kind of a fun experiment. Should be able to see a nice cone shaped spray, not lopsided off to one side or dribbling out.

Something like in this video below:



not sure this will work on your mopar tbi, but it works on the GM tbi.
 
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Hal effect.
Yea,you know,the thing.
The fuel pressure for that year is I believe 15 psi,1 year system.
I have the same year truck,it gave me problems too.
I fixed that.

20170830_183843.jpg
 
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So you never got back to me, did you pull the fuel filter and cut it open.

That TBI setup needs a good amount of fuel pressure too, would bet the in the take fuel pump is failing . . . low pressure.

Wonder where the fuel fiter is on that one, back at the tank like some of the newer cars ???

Pop a new fuel filter and try it again. Think that Dodge has a plastice gas tank, so that helps to prevent rust and sediment in the tank.
Water condensation in the tank though you need to change the fuel filter for that.

Good Luck.

------------------------------------------------------

If you have ever done any body and paint work you know your spray gun does not give you a nice fine mist at low pressure.
Same with the throttle body injectors, they need good pressure to spray a good atominzed pattern. Low fuel pressure is just going to dribble the gas in there like you are pouring it in with a spoon.

One Old mechanic showed me a trick with a timing light to watch the spray patterns of the throttle body injectors when you rev it up to about 1500 rpms.
It pulses the light as you shine it on the working throttle body injectors. You will be able to see if they are spraying nice with this technique.

Hook the timing light up to the battery + and - , then the lead on to number one plug wire. Give it a go, kind of a fun experiment. Should be able to see a nice cone shaped spray, not lopsided off to one side or dribbling out.

Something like in this video below:



not sure this will work on your mopar tbi, but it works on the GM tbi.

If you have a dial type timing light, it will light it up at idle. Been there done that. Works slick. think its 15-18 psi.
fuel filter is under driver side below driver. Be careful not to kink the lines when you change it. Guy replaced a hose, and kinked it. It would start and quit.
 
I would check fuel pressure and make sure the idle air controller is ok, when they go out the engine won’t idle or will idle intermittently from shitty to ok. I’m not sure but I don’t think it will throw a code when they go out.
 
I would check fuel pressure and make sure the idle air controller is ok, when they go out the engine won’t idle or will idle intermittently from shitty to ok. I’m not sure but I don’t think it will throw a code when they go out.
They are also notorious for problems. But dont go crankin around on it,unless you have a manual and set it by following the procedure.
Still doesent explain rough running. I would pull a couple plugs and see what they look like. i had an 88 ramcharger 10 years ago, it put me through the wringer a couple times.
 
I will throw a filter on today. Im sure its the original one. I tried the timing light deal. Didnt help much. Maybe it was to bright out at the time.
 
Check the codes again when it is acting up. In my W150 I also changed the TPS, really nothing else since I have owned it and also changed the injectors just because of the millage. I am lucky because a friend of mine has a ear=y code reader and it shows everything electrical.
 
I have a mac taskmaster for scanning obd1. I rarely use it, but its handy.
 
Think thats what he lent me goes into the connector under the hood? Gave me more codes than when you do it by the dash ight showing them. I would have thrown a ton of parts at it before I did the position sender. I really do not like that TBI system just have to eventually change it to a carb/ecu set up.
 
Think thats what he lent me goes into the connector under the hood? Gave me more codes than when you do it by the dash ight showing them. I would have thrown a ton of parts at it before I did the position sender. I really do not like that TBI system just have to eventually change it to a carb/ecu set up.
I wonder if a gm tbi could be installed in place of a mopar tbi.
 
Gonna start with fuel filter. Then pick up. My friend might have a scanner. I went through this before. I saved all the parts I took off when replacing trying to figure out what was wrong. What a pain
 
Borrow it before throwing more parts at it. Should show something if it is electrical.
 
Gonna start with fuel filter. Then pick up. My friend might have a scanner. I went through this before. I saved all the parts I took off when replacing trying to figure out what was wrong. What a pain
Ramchargercentral.com has an excellent knowledge base as well. Kinda like Fabo but for dodge trucks.
 
My 92 gmc was giving me fits, everything checked out,all i had left to check was the fuel pressure reg. even though fuel pressure wasnt bad.
all the sensors were acting within range,oxygen sensor was showing lean,causing longer pulse width on injectors.
So i went into the tbi.
B11DE7ED-1BDF-459F-8CB7-1F193D83D2AA.jpeg
 
I will throw a filter on today. Im sure its the original one. I tried the timing light deal. Didnt help much. Maybe it was to bright out at the time.

Throw a heavy drop cloth/sheet over the hood and front end to make it dark in the engine bay so you can see the timimg light pulses at the throttle body injectors.
 
Hopefully you find it, can be something really stupid like a dirty connection. How I found the dist connection was by accident. I change the two injectors and the truck did not start. I looked around the area I was in and I guess i was leaning on the wire and just by chance I was opening and re installing all the connectors in the area and the dist one was kind of disconnected so I opened it and the terminals were really dirty cleaned them put it together and the dam thing fired right up!
 
Hopefully you find it, can be something really stupid like a dirty connection. How I found the dist connection was by accident. I change the two injectors and the truck did not start. I looked around the area I was in and I guess i was leaning on the wire and just by chance I was opening and re installing all the connectors in the area and the dist one was kind of disconnected so I opened it and the terminals were really dirty cleaned them put it together and the dam thing fired right up!
I pulled it apart and it looked great. I keep thinkin the same thing. Something stupid would show up.
 
One guy online was saying it was his EGR valve that was causing all his problems, changed it all good now.

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Out of the ordinary, some are asking if the lock up torque converter is locked up not releasing?

Wonder if there is a way to temporarily disconnect that to test, like pulling a plug on the trans?

20201027_110940.jpg


3 pins on the plug = lockup converter
2 pins on plug = No lockup converter
 
I have the lock up converter. I can check the connection
 
Let us know if it is still stumbling at idle after you change your fuel filter.

Make sure you have 12 volts at your battery with a multimeter.
 
Still trying to figure out if this is fuel or electrical.

Try a couple shots of starting fluid at the throttle body throat as the engine is idling.

Tease it along adding a little more fuel at a time (start fluid), if the engine starts smoothing out you know it is a fuel related issue.
 
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