Hey everyone, new to dodge trucks, just bought a 1990 dakota 2.5 5 speed, having a weird issue. Truck doesnt like to start. But will start with carb clean/ starting fluid, etc and runs great afterwards. Also noticed the gas gauge wont go over 1/4 reading. Im thinking fuel pump, thoughts ? Anyone experience this ? Any help appreciated. And please let me know if this has been posted prior

 

Fuel pump and sending unit? Check fuel pressure to verify.

Welcome to DF!

 

Havent been able to find a complete sender unit, and dont have a pressure gauge to test it. Also previous owner claims pump was rebuilt back in feb. Never heard of a rebuilt pump though

 

Pressure gauge will be needed to properly test it. However, since the whole assembly isn't available, we have to replace just the pump and strainer on these.

Don't forget to check the inline fuel filter on the frame on a 1990. Hint: The 1992/1993 filter bolts up, filters fine, and ... has the inlet at the back, instead of the front, so you don't need a Ubend of gas hose.

RwP

 

Thank you RalphP, i did replace the fuel filter already and am still experiencing the issue. I am aware that a pressure gauge is necessary, but since i domt have access to one im trying to troubleshoot as best i can. Im leaning towards bad pump since it has problems on startup, regardless of hot or cold, but will run with no issues. If i understand correctly it takes more fuel pressure to start than is needed to stay running. I believe i saw that on another forum

 

Doesn't take any more pressure, but sometimes the line has to be reprimed.

Try this.

Turn it on but not to start, let it sit for 10 seconds, turn it off for 10 seconds.

Repeat twice more.

Then start it.

If it starts, it's just losing prime.

You can repeat this, or get a pressure gauge and see if it's the regulator or the pump.

(I'd be the regulator since the pump is fairly new.)

Regulator is on the TBI unit; here's what it looks like (and one possible source for it): https://www.rockauto.com/en/catalog/...regulator,6124

(Yes, it says 1988. Notice the interchange is through 1991, and since my bookmark is for a 1988 ... )

RwP

 

Ill try that tomorrow, and im not certain if the pump is new or not. Prev. Owner didnt show any paperwork for the pump being replaced.
and ouch, their regulator is almost as much as the parts store lol. I was hoping it wouldnt come down to that

 

Ah.

Well, it could also be the pump back draining.

Only way I know to test is to crimp off the fuel line as soon as you shut it off (with a crimp off pair of hose pliers; such as these at Hazard Fraught: https://www.harborfreight.com/radiat...ers-99704.html ) and see if it loses prime that way.

If it doesn't, it's the pump. If it DOES, it's the regulator, or an injector hanging open. (THAT - injector hung open - is probably not the problem on the TBI units. Never heard of one doing that, anyway; HAVE heard of EFI injectors hanging open a slight bit).

RwP

 

Its definetly not the injector, i had someone cycle it off and on the other day and i watched the injectpr when it was shut off, i didnt see any leakage. So if i clamp off the lines and it starts it then pump ?

 

Just about every 1990 2.5L I've seen has a broken fuel gauge. The sensor burns out - leaves a nice singe mark on the pump. As for the hard start, are you getting any sputtering or backfiring? Being close to 30 years old, you might want to double-check that the timing is still on (electrical and mechanical). I really don't know where to find the ignition timing marks though. They're long gone from my engine...