sluggish acceleration

[bludmon]

Hey guys I have a couple of questions for you. I have a 93 explorer eddie bauer edition that I just recently picked up. It has 194,000 miles on it but it runs great! I just took it out on a long road trip and noticed that getting over 55 seems to be really making the truck work pretty hard. It seems that the truck has a hard time getting into 4th gear and staying in fourth. It doesn't slip but when it shifts sometimes you can feel it go into fourth gear and other times you have to watch the rpm's to see if it engaged or not. Whenever I go up a hill it will downshift but it just seems that I almost have to floor it to get it past 55. This may all sound normal to most of you but I just don't think I should have to make my engine work so hard to get up past 55. It almost feels like something is holding it back. I just cleaned my MAF,adjusted my iac(which is just like my mustang) changed all plugs and wires,changed my air filter and fuel filter. It also has a totally new exhaust. What else could I do to get some "pep" back to my truck? I realize I have 194,000 miles and I'm not going to win any races but it just seems that it doesn't have alot of "spunk" after 55


I just sold a toyota corolla that had 200,000 miles on the engine and that seemed to have more spunk then my ex. . Yes, I know totally different car and totally different circumstances but I hope you can get what I'm saying.

 

[Masterd]

Interesting.... looks like you've done everything that I would have recommended.

Well they only made 160 horses at the crank, at their best.vBut I'd never describe mine as sluggish.

 

[bludmon]

The only thing that I haven't touched is the egr valve. My wife took it to work and said that it stuttered when she took off. I know it wasn't because it was cold since I just got done driving it. Is the egr valve easy to take off and clean? It also idles at 1000rpm's and I cannot figure out how to get that idle down any further. The only thing I haven't done is adjust the idle screw(if there is one)

 

[Masterd]

Try cleaning the IAC again, and looking at your oxygen sensor. Its probably really old by now.

 

[jtb1689]

I am by no means an expert on this stuff but just a suggestion (and please, feel free to add or discredit this), have you checked the throttle body to see that the cables are right? I have heard and read up on some throttle bodies not sitting right and if the cable to the accelerator isn't short/tight enough maybe its just that you aren't opening your throttle body all the way even when it's floored. Take off the intake tube from the throttle body and check to make sure that when someone pushes the pedal to the floor that your throttle body butterfly sits completely horiztonal (you can do it when the car is off). Just a thought.

 

[troy11556]

another thing is listen and look for any vaccume leaks. they can cause it. remember your tranny has a vaccume line running to it. and if it has a leak then it will hav trouble shifting. the other thing i would have the compressions tested either by you or someone else.

 

[Robrt32]

Mine is definitely not sluggish.... Ive had it way past the 85... You have already done what i would check....

 

[troy11556]

lol i had mine past 85 to. i had a 93 blazer with the 4.3L vortec that would have trouble passing 85. but i would still check for a vacume leak.

 

[bludmon]

Thanks alot for all your comments and suggestions! I will clean my iac again and see if that helps. Just another stupid question--I have another iac from 1988 Mustang that looks exactly the same as the one on my ex. Will that work on my 93 Explorer?

 

[pugsy]

I am by no means an expert on this stuff but just a suggestion (and please, feel free to add or discredit this), have you checked the throttle body to see that the cables are right? I have heard and read up on some throttle bodies not sitting right and if the cable to the accelerator isn't short/tight enough maybe its just that you aren't opening your throttle body all the way even when it's floored. Take off the intake tube from the throttle body and check to make sure that when someone pushes the pedal to the floor that your throttle body butterfly sits completely horiztonal (you can do it when the car is off). Just a thought.

Along the same line, but the common problem is slack in the throttle cable. Get under the dash and see how much slack is in the cable connected to the gas pedal. Keep in mind there's 2 cables and one is the Kickdown cable for the tranny, it's supposed to have some slack.

Do a search on here for Throttle cable mod/fix. There's some posts around on it. But as mentioned above, the slack will cause the throttle blade to not open to WOT...ie. less power.

 

[boggs1227]

pugsy is right about the cable mod/ fix for the gas peddle.when i got mine it felt like i had to give it alot of peddle to get the truck moveing ( now keep in mind this is when my transmission was needing rebuilt ) after takeing up the slack in the cable it felt like driveing a new truck ....instant throttle responce .

this is def something you have to do because like stated ,with age and years of stomping the peddle ,the cable gets longer and the butterfly does not open all the way .

 

[bludmon]

Thanks alot guys for all your help! I cleaned the IAC again and it definetly helped. When it is cold it will idle at about 1000rpms but give it between 3 and 5 minutes the idle gradually comes down to about 700 to 750 rpms. Should it take that long in cold weather? not that I'm concerned about it too much--I'm just happy the idle came down to a normal spot.

I'm going to start searching for that posting about tightening my throttle cable. Thanks again for all your help and advise!!

 

[jtb1689]

It's around the mid 30's to low 40's around here when I have been starting my car and it takes a while to get down to normal rpms. Likes to stick around 1000 for a bit and I like to think my engine is running decent aside from the under load pinging. So I think you're ok on that

 

[bludmon]

I tried that fix for a stretched throttle cable and boy did it work wonders!! I feel like I have a new truck!!

Thanks for the great info jtb1689 and pugsy! Also thanks to everyone else that had suggestions--It is GREATLY APPRECIATED!!

I do have another question that I have asked before but never really got a good answer on. I do a in-town paper route(for a major paper) that will have me constantly idling,stop and go,and shifting from forward and reverse for a good 90 minutes a day. What is the best way to protect my engine and transmission so I don't have any future problems. I just recently changed my oil using 4 quarts of valvoline and one quart of Lucas oil stabilizer. I'm not sure if I should even touch the tranny considering I don't know whats been done to it before I received it--again there is 194,000 miles on it. I was thinking of running some Sea Foam thru the brake booster or pcv line to maybe clean up the valves a little. Any (more) suggestions?

 

[Masterd]

Is it an auto?

If so, theyre known to fail. If the fluid isnt totally black or anything, I recommend changing or flushing it. If the fluid is totally wrecked, generally you dont want to touch it.

 

[bludmon]

It is an auto. When you look at the fuid it is has a light shade of red almost pink color to it. The ex does seem to shift ok from what I can tell

 

[Masterd]

That means it should be in good condition. I'd say no need to mess with it.