Hmmmm Throttle positioning sensor??

 

Well I reset it at lunch and during the drive home the CEL did NOT come back on. I've not taken above 35 and will not do so until AFTER I get her through emissions.

So I'm wondering if the misfire only happens at highway speeds, since both times it has come on has been at highway speeds.

Wondering if it's an injector. Especially if it's the same cylinder each time. Next time I'm at the wrecking yard I'll pickup a handful unless I get the promotion at work this week in which case I'll grab one there until I get the paychecks from the raise then I'll get a new set and hand over a fistfull of cash to drop the cost of it down then I'll buy the lift and tires. WHEEEE!

 

There are better injectors than the stock ones. PM Bustedback. I think he used Dodge Neon injectors.

 

I have a funky miss as well in cylinder 1. I haven't determined if it's the coil or injector

 

My brother is a jet engine mechanic and he said the fuel injector nozzles have to be "patterned" every so often, that is tested to make certain the spray pattern is right for a clean burn. Your injectors probably could stand to be replaced just because of their age. JMHO.

 

One other thing to consider the jeep did sit for a couple of years. It's fairly obvious when popping the hood.

If I had the $$ I'd pickup a set of injectors but at best they are 3 months off, and at worst 2 years or a little more. Until then it's wrecking yard parts.

 

I got my 703 injectors from a couple of 95 Dodge Neons for free (cargo shorts pockets are a great thing) at the local you pull it yard. A few cans of brake cleaner to clean them up and new O rings. I have less than 20 bucks invested in my fuel injectors and they have caused me no problems.

 

Busted, I KNEW we were of the same mold! I can't tell you how many things I've copped from junkyards.

 

Yeah been thinking the same thing, but the way the TPS sensors go out I've heard I'm thinking of just buying one new. Injectors yeah JY, but what about the TPS? They are 32 bucks new. I have the money but I am strapped right now pretty bad and will be until this thing is paid off, I get a promotion, or find another job.

 

215k on my original TPS sensor. I don't know why so many people seem to have issues with theirs.

 

The crazy thing about newer vehicles is that they will have similar problems but different issues. I have gotten to a point with some of my older toys, that if the part is relatively cheap and not to difficult I will do it just as maintenance. I went through hell with my dodge ramcharger with a similar issue, and probably spent $100 in various parts, but really they were near the end of the cycle on a 25 year old truck......the goofiest things that I have struggled with was actually a fuel pump that was giving me symptoms of electronic items.....go back to the basics on her. Disconnect each cylinder one by one for difference

 

If it wasn't an intermittent thing and hard to detect when not at highway speeds, I would have done that already.


The things making me think TPS, it basically shuts down at 45MPH and starts vibrating pretty bad until you let off the throttle a bit. If you step back on it, it works normal for about 1.5 seconds and accelerates fine, then starts again. If you stomp on it she will actually take off, but then after about 4 seconds it will start misfiring pretty bad. In town it can't decide smooth or rough. It also gets about 7-10 MPG when featherfooting it. I realize it's not a gas sipper and isn't supposed to get great mileage, but it should be doing ALOT better then 7! It also seems to hunt for gears sometimes, as well as it likes to hesitate when taking off and when changing speeds. I know there are many things that can cause each individual symptom I have listed here. However very little is capable of producing all of them.


I'm not looking to start a philosophical debate as to what parts can cause what kinds of issues etc. The point is I'm not swimming in cash, I need to get to and from work and smooth this thing out and stop the misfiring. I can't start shotgunning the heck out of it as I don't have that kind of dough at the moment. This truck SAT for a good 2 YEARS. After the tuneup is the TPS a good place to start considering the above symptoms, and should I pick up a new one rather then JY it?

 

I would lean that way of the TPS...it's the only thing that will act up at a certain set speed like that. I would get a new one because I once bought a used part and installed it. I then went after everything else, but the used part was actually bad as well.....also take a glance at vacuum lines and clean the mass air flow sensor....good luck

 

Read your post at work, couldn't answer it though. I grabbed one on the way home along with a can of MAFS cleaner. Though the MAFS is not anywhere on this thing I've ever seen them before. I'll have to find it. I'm used to seeing them on the air cleaner ducting. I won't be able to replace the part or anything until tomorrow at lunch time.

Thanks a bunch.

 

You don't have a MAF sensor, you have a MAP sensor. It measures engine load by a vacuum signal.