98gt P1443 Evap Purge Issue

broncojunkie

Active Member
Apr 12, 2014
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I recently picked up this 98gt, which was in need of a bunch of minor fixes. It had an engine miss, which I fixed with some new plug wires and replacing some hoses going to the purge cannister, purge valve, and throttle body. The hoses were in terrible shape. After fixing these issues, all codes disappeared and cel went off without having to clear it manually.

After driving the car for a week or so, I got a cel again and P1443 came back (no other codes). I've been reading through old threads on the purge sylenoid, cannister, vacuum hoses, etc. When I was replacing hoses, I checked out the purge cannister and it appeared to be in good shape with no crack. All hoses up front are now brand new. The wife has been commenting that it smells rich, when running. I finally noticed a slight gas smell today, when she was driving and I got out of the car in the driveway from the passenger side. This is near the purge canister, so I'm wondering if I overlooked something there. I also couldn't help but notice that the gas cap itself looks a little rough, although the sealing surfaces look to be ok.

I tracked down a p1443 on my '02 Explorer a couple years ago and it turned out to be a small rust hole in the filler neck. What's the best route to start tracking this one down? Can the purge valve itself be cleaned? Tested? Can a faulty valve or sensor (I believe those are two different parts, right?) cause a gas smell?

One more thing....the gas smell really doesn't smell like raw gas, but more like unburned fuel. I did pull plugs when I replaced wires and they all looked fine. No symptoms of running rich. The car seems to run great now, except for a very slight miss every now and then.
 
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I have some experience tracking down and resolving a similar issue on a 96 GT. Very frustrating because the same DTC "could" be caused by a number of things. Some of the lesson learned are:
  • The purge flow sensor fails in a great number of cases. Gas vapors are very hard on parts. The purge flow sensor is cheap enough to replace just to rule it out during trouble shooting. Do yourself a favor and replace it if not done already.
  • EVAP leaks are very hard to find. In many case it's necessary to perform a visual inspection on the entire gas vapor system replacing every rotted vapor line found.
  • The filler neck rusts out in a large number of these older cars. Same for the gas tank filler neck grommet.
  • The EVAP solenoid can be easily functional tested off the car. You should not be able to blow through it when no power applied. Apply 12 volts and you should be able to blow through it.
  • This DTC is hard to trouble shoot because of the length of the drive cycle needed to make the PCM perform an EVAP purge. Sometimes many miles are needed. Search on "drive cycle" as there are ways to speed it up. When working on my EVAP problem I got to where I could complete a drive cycle in only a few miles. Much faster.
Good luck.
 
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Thanks for the tips. I have an update on this. After going over some parts and double checking hoses and electrical connections, I cleared the code and drove it for a day or so. The cel came back on after some time. I looked under the hood again to start checking and found that my new cai pipe had come apart between the maf and throttle body. I guess I was in a hurry when I put it on and didn't fully tighten one of the clamps.

So I fixed that mess and then removed the purge sensor and valve. I cleaned them both out with a good flushing of carb cleaner. Checked the codes and I was getting P0443 (Evaporative Emission Control System Purge Control Valve Circuit Malfunction) and P0171/P0174 (System too lean bank 1 and 2). I drove the car all day yesterday and the cel hasn't come back on as of yet, although, I have noticed a slight miss from time to time.

I'm hoping if I drive it some more, It will either clear up or throw another code, telling me what's causing it.

I also checked out the filler neck and tank areas yesterday. There looks to be the slightest bit of moisture around the tank grommet, where the filler tube enters the tank. I plan on replacing that. The rest of the area, although a little crusty, appears to be leak free.