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98 GT evap system leak

The fuel pump in my 98 GT died awhile back and I paid about $700 to have it replaced. The high price reflects the fact that the pump is in the tank and the whole tank needs to come off to make the change. (Someone will have to explain to me why this is good engineering.)

In any case, shortly after the fix, the MIL goes on with P0455 "Gross Evap Leak" DTC set. I take it back, and, of course the geniuses at the garage just clear the DTC and tell me to go home. (I could have done that myself!)

Anyway, a couple of weeks later, the MIL's back on with the same DTC. (It took a couple of weeks because I seldom drive the car. I'm a grad student and do a lot of walking lately.)

There was no problem with the evap system before I had the pump replaced. It seems pretty obvious that they screwed something up when the dropped the tank. I'm having a hard time getting the garage to take this seriously or to accept ownership of this problem -- which they obvious caused.

It's not a driveability concern, but it *is* necessary for smog in CA, and so it's an real ownership concern.

Anybody have ideas how to get this fixed *cheaply*? I don't think the garage that did the fuel pump has a smoke machine. If they did, it would take a few minutes to find the leak and tighten/replace whatever went wrong.

And for god's sake, no, I did not forget to tighten the gas cap! I understand that is a frequent source of this DTC, but it's not relevant here. I have had the car for 9 years and have never had this issue before, now it appears chronic.

Any help or tips are appreciated!

thanks, dave j

Reply to
Dave J
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Electric fuel pumps are submersed in the fuel tank I believe for performance (of the pump) and safety issues. Most fuel injected cars are recent designs and the tank is located under the back seat and is easily removed through the interior by way of an access panel that is exposed by removing the seat.

However, the SN95 mustang layout evolved from the FOX platform, which was designed for carburated engines. The fuel tank is under the trunk. This why the whole fuel tank needs to come out of the car to access it.

IMO there should have been a removable panel in the trunk floor that when removed exposed the top of the tank where the fuel pump is located and allow it's removal through the trunk. Why that wasn't done I am not sure. But I'll wager it was because of cost, post crash fuel fire risk to passengers, and/or structure of the unit body.

They missed a hose connection or caused a sealing issue somewhere probably.

Of course.

Cheaply depends on where the leak is. The shop should take care of it.

It may be where the filler pipe enters the tank.

Reply to
Brent P

they should have replaced the tank to filler neck seal, can't reuse it, always leaks if you do. They should have charged you $27 or so for it, should be on the invoice as a part cost.

Reply to
Loman Napetos

Okay, so the garage just called me back and told me that he thinks it's the evap system purge valve. He thinks it'd be $65 for the part and another $50 for labor. He says it's /coincidental/ that this valve (which is located somewhere up front -- I don't have my Chiltons in front of me right now) failed at the same time they changed the fuel pump.

Mind you, this diagnosis was performed on the phone, based only on the DTC. Other than hooking up the reader and clearing the code from last time, they have not seen the car since the issue came up. He says he's seen this 100 times with various Ford products.

Argh!

-- dave j

Reply to
Dave J

It's not. the purge valve has it's own code. The motorcaft part cost me about $10 retail when I replaced it. It's two hoses and an electrical connector and pretty easy to get at under the hood. Takes 5 minutes.

$115 for that.... I should be a mechanic... jebbus.

Reply to
Brent P

Well, now after googling on it for 1/2 hour, I am not sure if it was the "vapor management valve" or the "evap canistor vent solenoid" he was talking about. There appear to be two valves in the system, one normally open, the other normally closed. In any case, yeah, if I can do it in 20 minutes (I'll inflate your 5min estimate by 4x for my general cluelessness under the hood), I'll give it a try myself.

But I also suspect, as you do, that this is not the case. Another poster (Loman) mentioned that it could be a gasket where the filler tube meets the tank. That's interesting, as I did not see that part on the invoice after the pump change. On the other hand, that it's curious that the leak from that gasket would be large enough to cause the "gross leak" code. I'd expect to see a few drops of fuel when filling if the gasket were seriously damaged.

-- dave j

Reply to
Dave J

What kind of car do you have?

I looked up the part online and saw that it was about $31 -- $65 from the dealership. What's more, in my car (98 GT vert) it is not under the hood. It's under the right fender, mounted near the charcoal canister. The whole fender needs to come off, which unfortunately requires the front bumper to come off, as well as headlight and foglamp, and about 30 little clips and screws.

Not a five minute job. Sometimes I really loathe this car!

-- dave j

Reply to
Dave J

Wow, I should pay myself $700.00 ha! I had a shop install an after market pump back in 01 and they rolled the gasket that seals the cover for the pump. On my first fill-up gas poured on the ground till it got below the top level. I would think something like that could cause an air leak setting off the code. I later replaced that pump myself with the stock pump (I use a KB Boost-A-Pump)and never replaced the filler neck seal without ever a problem.

Reply to
GILL

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