2002 Stumble, hiccup or hesitation between 1500 -2000 rpms @ 35-40 mph

[stevedaphotoman]

After getting my power steering pump replaced last month, I noticed a sight hesitation from the engine at about 1500 0 2000 rpms when the engine in under a slight load or slight incline with little or no acceleration. A little background, when I had the T-Bird towed in for the power steering pump, it was during a heavy rain storm. Right after picking up the bird from the garage after the pump replacement, I took it to the carwash to get dirt and grime off it. At that point within a few days, I started getting the hesitation. Driving down the highways at 55-70 mph it runs like a top. It’s just at the 1500-2000 and about 35-40 mph. There is no check engine light on.

The story thickens. I went to check the gas cap and the gas cap was loose, not fully “clicked” engaged. It was over the filler pipe but loose. So I ran a can of Seafoam thinking perhaps some water got in the tank. The tank was at ½ full so adding the 16 oz. can of Seafoam was perfect dilution for aggressive water removal of 2 oz.’s per gallon. I drove it till almost empty and it seemed to get better, I refilled the tank yesterday and added one can of k-100 to catch whatever water there may have still be in there, if there was any in the tank in the first place. I took the car out for a spin, and she ran flawlessly except for one very small stubble at the usual 1700 rpms @ 41 mph.

I know I should have a scan tool, which I will buy this week to check for codes. I thought, could it be fuel pump? I just had the fuel filter replaced about 4 months ago. Then I thought I would have more hesitations over the entire driving range. Same with a spark plug and COP issue. Then I thought perhaps the throttle position sensor or throttle body needs cleaning. With 21k miles on the clock, it could of got fouled when the power steering pump went and spewed out oil when the power steering pump bearing let go.

Any ideas? Oh and BTW I confess, I was the Bozzo who didn’t put the gas cap on tightly in the first place some 2-3 months ago after the previous fill-up. The gas cap light never came on either.

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[Gus Gutz]

I fill up weekly. I don't know how you can go 2 to 3 months.

 

[stevedaphotoman]

I fill up weekly. I don't know how you can go 2 to 3 months.

Upstate NY so you automaticly hack off 5-6 months for snow and crappy weather. Then it's not our daily driver. So that's a minus 3000 - 4000 miles.. That leave em with about 1200 miles a year, times 300 miles per fill-up leave me with 4 fill-ups a year.. Divided by the Covid factor of 2 equals on my 3rd fill-up for the season.. 😵 My head is hurting now.. Mine is second from the right or is it the far left one.. Darn, I can't remember my own bird..

 

[The Flash]

did you have the cops changed out/when with OEM part? have the plugs been changed?
the gas that is 3 months old may have gone bad. Yes, it needs a scan. I have found that 2002 doesn't give as much info as the later TB's. and they don't give that much info compared to my 2011 caddy.

 

[stevedaphotoman]

did you have the cops changed out/when with OEM part? have the plugs been changed?
the gas that is 3 months old may have gone bad. Yes, it needs a scan. I have found that 2002 doesn't give as much info as the later TB's. and they don't give that much info compared to my 2011 caddy.

COPS and Plugs are probably original as I bought the bird with 16k on it and now it has 21k. I have never changed them.. I need to go out and buy a scanner. The previous time I filled the tank was late May or early June and it was just yesterday that I filled it up again.. I do use premium and non-ethanol fuel.. We can still get 91 octane non-ethanol gas here. I also add gas sta-bil in with the tank especially over the winter storage but usually not over the summer driving months.

 

[The Flash]

I get my stuff on line, OBDll cost about $70.

 

[ESHAWE]

Had a similar problem in my 02,ended up being 2 leaking sparkluf coils, my a.c. was off kilterbalso

 

[Kjbleau]

Upstate NY here too, hope you are the one that doesn't have a front plate, I'll wait for the ticket before I deface her beautiful snoot

 

[highwayghost]

My F250, 6.2 L just started doing the same today, stumble at 1700-2000 RPM, light load. It recently had to have the PCM replaced. If it stumbled before replacement it was not as noticeable. My first thoughts are to clean the MAF sensor. Just ran the OBD and confirms several misfires on cylinder #8 only. I just replaced all 16 sparkplugs. Time to replace the 8 wires. It has COPs and a wire to each extra plug. I have a spare COP, If wires don't help I will put the COP on #8. If I find a fix I will post.

 

[Mach5]

COPS and Plugs are probably original as I bought the bird with 16k on it and now it has 21k. I have never changed them.. I need to go out and buy a scanner. The previous time I filled the tank was late May or early June and it was just yesterday that I filled it up again.. I do use premium and non-ethanol fuel.. We can still get 91 octane non-ethanol gas here. I also add gas sta-bil in with the tank especially over the winter storage but usually not over the summer driving months.

Dude! Stop running around chasing phantoms! Buy the scan tool and find out what's going on!

 

[Frankie the Fink]

I'd run a tank of premium with some Techron additive through it before I went medieval on swapping parts....could just be a dirty injector.... Pays to try the simple stuff on the car before shooting it with the "parts cannon".

 

[stevedaphotoman]

I'd run a tank of premium with some Techron additive through it before I went medieval on swapping parts....could just be a dirty injector.... Pays to try the simple stuff on the car before shooting it with the "parts cannon".

I used to use Techron all the time but just recently I started to use Seafoam.. Not sure which magic elixir is the way to go.. The internet is chuck full of testimonials Of all of them..

MODERATOR NOTE:

 

[Frankie the Fink]

I've used Marvel Mystery Oil, Seafoam and Techron over many decades and have settled on Techron as my "go to" fuel systems cleaner for modern cars... It has a slight edge over the others from what I've read (and that's a lot).

Dealers and the quickee lube joints offer a fuel system cleaner service but its often pricey.

I did a dealer fuel injector/throttle body cleaner discount deal at my Toyota dealer for my Tundra and it cleared up a rough idle issue that NONE of the other magic additives did - just as a data point.

MODERATOR NOTE:

 

[stevedaphotoman]

I did a dealer fuel injector/throttle body cleaner discount deal at my Toyota dealer for my Tundra and it cleared up a rough idle issue that NONE of the other magic additives did - just as a data point.

I have a feeling that may be my issue or the throttle body sensor.. I am going to buy a scanner and see if there are any codes stored.. What should I look for in a scanner,.. Do I need a $100+ one or will a sub $100 be fine. Will I need a shop manual to find the codes issue readout, or are they generic across the manufactures and stored in the scanner? Will a Harbor Freight scanner do the trick or should I go to a auto parts store.. I will probably just use it to inform me on what is going on, and not necessarily open a repair shop..

 

[Frankie the Fink]

Don't screw around - get the BlueDriver scanner from Amazon and it'll do all you need. It'll show the codes stored and dig into the cloud database to find what that means for your year/make car and give a list of the things that were previously done by owners of the same car to fix the issue. No manuals or Buck Roger's decoder rings needed.

Its $99 and you can use it on any car in your fleet.

I have two of them...