Fuel Pressure Fix without buying whole module

xlrashn

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Hello all, I am new to the forum but wanted to share my fix for the fuel pressure drop issue and extended crank. I have a 95 RT10 with 18,000 miles and found mine having the issue. I have noted on these forums many people saying that you have to buy the whole fuel pump/module assembly to get the fuel pressure regulator to fix this problem. I own and auto repair facility and I had my service writer call the local Dodge dealer and they said they could order just the regulator itself. We had them do so, and indeed just a regulator showed up. We installed it yesterday and all the problems are fixed. The car starts right up instantly hot or cold. The regulator is Dodge part #4746407 and my cost on it was $63.77. Alot cheaper than the module! The repair only took about 2 1/2 hours and went smooth. Hope this info is of benefit to others.
Jim
 
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xlrashn

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Mine is a Gen1 95 model. As far as if this is new, I am not sure. I just called and asked and they delivered. If you need one I included the Mopar part# in the original post. They must be available to all I would think.
 

whitebluevipe

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so your problem was that you had to turn the key 3 or 4 times before it would start? i just want to make sure it is the same problem i have with my 96 with the check valve being bad. also chuck .T are you out their to answer in on this?
 
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xlrashn

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Hello whitebluevipe, mine was not holding pressure at all after key off. I would have to crank it 3 to 4 times before it would build enough pressure to start. Also I had a rough idle situation that was also caused by the regulator that cleared up too. The old regulator was holding the fuel pressure at 65psi which is 10 lbs too high. Therefore the engine was getting more fuel than it should and was loading up a little at idle. After the new pressure regulator was installed it hols a steady 55psi and will start within 1 to 2 seconds every time.

Jim
 

Johann

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The 4746407 was only used from '92-'95, starting in '96 the check valve isn't in a separate component it's in the fuel pump module.
 

Shelby3

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The 4746407 was only used from '92-'95, starting in '96 the check valve isn't in a separate component it's in the fuel pump module.

I have a 96 GTS and had the same problem fixed by replacing the regulator on top of the fuel module assembly.
 

Tom F&L GoR

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xlrashn, how did you access the top of the fuel tank?

For any model year, here is a $100 fix that takes about 15 minutes:
http://forums.viperclub.org/showthread.php?t=592342&highlight=primer+timer


186Primer_Timer_instructions.jpg

186Primer_Timer_Install_Pics.jpg
 
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xlrashn

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Tom,I removed the tank per the factory repair manual. I did however only slide the tank into the trunk area for the part swap. There really was no need to remove it completely from the car.
 

Johann

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I have a 96 GTS and had the same problem fixed by replacing the regulator on top of the fuel module assembly.

The info I posted is from the factory parts book, it shows the regulator as part of the module only and '97 and later doesn't even show that P/N.

In any case, Tom's Primer Timer is a lot easier than getting to the module.
 

z76232

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I had this same problem and purchased the fuel pump extender from Tom and have not looked back. It makes the pump run for 12 seconds instead of a couple. I need to adjust it so it runs for about 20 seconds and it would be perfect. I just cycle it twice. Tom said I could do this but I haven't got around to it yet. Very low on my priority list. Tom's a great guy to work with and his product is first class. He's not lying when he said only takes 15 minutes to install. We did it in 12. Bought his upgraded rear brakes at the same time. Sells only first class stuff.
Dave Prine
 
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xlrashn

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I can understand using the timer solution for a quick fix. However, in my opinion it is just a band-aid masking the real problem. I am more of a purist and want things to work the way they were originaly designed. That is why I chose to go the route I did. It is just my preference.
 

Tom F&L GoR

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I agree; it's a bandaid and a diagnostic tool to determine what the problem really is. And depending on your schedule, it can get you through a driving season or let you get by until you want to spend the money and downtime. If it were a real vehicle performance issue things would be different.

Any chance you looked at the old part to see what happened?

And it's interesting how other cars normally run their pumps much longer than 1 second....
 
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xlrashn

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My experience has taught me that disassembling the regulator would destroy it and probably yield no clues. However, training has also taught me that the only thing in there that could be bad is the check valve (for the bleed down issue) and a weak spring (for the 10lbs over spec fuel pressure). As far as the length of time for fuel pump priming, 2 seconds is and standard for a majority of the industry. Even knowing that, a bad check valve is going to create an issue no matter what the factiry setting is. The extended run time kit being spoken of is the only way"around" the issue. Still going to have to fix the cause sooner or later, and not just the symtom.
 

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