Sputtering while accelerating

[84fiero4speed]

This morning when I started up my car, it refuses to accelerate below 2500-3000 RPM. Its a 93 ES with an auto. When you hit the gas, it feels like it only has 3 cylinders and it idles rough when in gear. As soon as it gets past 2500-3000 RPM it picks right up and runs fine. I have no mods on my car and I have replaced the spark plugs with Bosch Platinum +4. IAC servo replaced last summer w/mitsubishi part. Replaced the PCV and it didn't help. Maybe just bad gas? Any help ASAP would be great, I'm stuck!!
-Aaron
PS also cleaned out the injectors with 3M Intake Cleaning System so I don't think its dirty injectors

 

[RipperXX]

Change your O2 sensor lately?

 

[84fiero4speed]

No I haven't, but wouldn't that cause the check engine light to turn on? I thought about the O2 but ruled it out since the light didn't turn on, I'll replace it anyway since they cost like $3. The car only has 56,000 miles on it so it shouldn't be anything too serious. What about a stuck valve? It happens a lot more frequently when its in gear if that helps any.....

 

[RoasT BeeF]

Hmm sorry I have no info to contribute to you problem but just thought I would tell you that from what Ive heard you really shouldnt run platnium plugs on a DSM. Use NGK's.

 

[84fiero4speed]

I wasn't too sure what plugs to buy but the guy at Checker reccomended the Platinum +4. He said he was running them in his Talon and they worked great. They've been working fine for the past 3 months so those should be fine. I retract the previous statement about the $3 O2 sensor, it costs $48. Ouch!

 

[Doug99RS]

I wouldn't recomend the platinum's either. While you were running them before, that doesn't necessarily mean that they aren't the cause. Plugs are cheap enough and easy enough to replace to justify doing that first.
Doug

 

[Defiant]

Find a nice, deep pond for those Bosch plugs, and get NGKs. The platinums are a _definite_ taboo for turbo cars, but it sounds for all the world that you've eaten your set in three months without boost. It's the easiest, cheapest first fix.

Let us know.

 

[lexrockhard]

Man, I'm having the same problems. No indicator lights going off, just sputtering when i accelerate hard. It seems okay if i warm up for a few minutes and accelerate steadily after that. I replaced my bosch spark plugs (that i've used for awhile) with NGK's, but it's still happening. I just went through one treatment of the fuel injector cleaner this past week, I'm going to put in another treatment tomorrow.

My car's stock too (5-speed).

 

[84fiero4speed]

I'll try the plugs. I pulled the O2 sensor and tested it, its resisting to about 12 ohms which is what its supposed to. The guy at Advance Auto said that it sounds like I'm running really rich and that I should check the EGR valve and the whole EGR system for vacuum. Thats my next step for today. I'll keep you posted.

 

[84fiero4speed]

Well I pulled the plugs and they were totally shot after 4,000 miles. I went and got NGK V-Power and put those in. It seems to have fixed the problem. Thanks guys, I don't know what I'd do without this site!

 

[King Salami]

Don't forget the plug wires. I had an acceleration/shuddering problem similar to yours - it turned out to be the plug wires.

 

[84fiero4speed]

Remember how I thought it was fixed? Well that lasted about 15 minutes. As soon as I started it up this morning, it started doing the same thing. It seems to do it more once the engine has warmed up but it still happens. Does anyone else think it might be the EGR Valve? Is there any way to check if it is plug wires whithout buying them and putting the new ones in? I don't have a whole lot of money to keep on buying parts that fix the problem for a day. I guess I can get a EGR valve just to try out from the salvage yard but the cheapest I can find plug wires in town here is $45.
Oh yeah, not sure if I mentioned this before but the car olny has 56K on it so it seems a little soon for the EGR valve to go out.....

 

[99gst_racer]

Yeah, my buddie's truck was shuttering on acceleration just like your DSM and his was because of a clogged fuel filter. Now my DSM is doing it too, mine only does it above 5K RPM w/ over 50% throttle. I am going to change my filter very soon and hopefully it fixes the problem. (P.S. - the filter is near the base of the battery)

 

[Morphius]

Check your parts in this order:

Plug wires
Fuel pump
Fuel filter

My guess is the fuel pump from my experience this past week.

 

[84fiero4speed]

Ouch, fuel pump was one of the things I was hoping wouldn't be on the list of things to check. Fuel filter seems likely since after looking through all of the recipts from the pervious owner this weekend, fuel filter was never on them, and he saved everything. So as far as I know my car has 56K on the ORIGINAL fuel filter. Time to start checking stuff out I guess, I'll keep you posted......

 

[Morphius]

Originally posted by 84fiero4speed
Ouch, fuel pump was one of the things I was hoping wouldn't be on the list of things to check. Fuel filter seems likely since after looking through all of the recipts from the pervious owner this weekend, fuel filter was never on them, and he saved everything. So as far as I know my car has 56K on the ORIGINAL fuel filter. Time to start checking stuff out I guess, I'll keep you posted......

My daily driver has 189K and still runs the original filter. So, mileage isn't a good test for that. Comes down to how dirty the gas you put in your car is. And obviously you can't control that. You'd never know.


-DaimlerChyrsler Engineer

 

[Doug99RS]

The EGR valve will most of the time cause a surging at highway speeds that feels like a single cylinder mis-fire that does not happen every time that cylinder fires. You can look at the spark plug wires sometimes and see lightened or white spots on the wire insulation. The light spots are signs of heat and electricity jumping through the insulation. At 56K if they are original then you are probably due for a set anyways.

Another condition caused by the EGR valve is poor idle or start and stall condition. Frequently the intake manifold will get extremely hot as well. This is caused by EGR gases being routed back in to the intake manifold when they're not supposed to and causing the engine to stall. Sticking a BB or nail in a vacuum line won't fix this condition unless the egr solenoid is stuck causing vacuum to be applied to the egr diaphram. Most of the time though the valve is physically stuck and vacuum to the solenoid is not an issue.

The fuel filter is a pretty good idea but as preventative maintenance only. I've not seen any clogged fuel filters causing a problem in really... any 95 and newer vehicles since I've started working on them 5 years ago. The newer cars have very fine filters on the pumps and most of the time the filter will starve the pump for fuel and burn the pump out before the main fuel filter actually gets clogged enough to cause a driveability problem.

So that kinda backs up morphius on one side of his point. And on the other side I've a handfull of cars where the tank had water in it from the filling station. Taking a sample of your fuel, from a fuel line at the engine compartment, can be helpful. Simply fill a clear container with fuel and let it sit for a few minutes. If the fuel starts seperating from another liquid in there then you know you've gotten contaminated gas.

I don't think you'll want to put a used EGR valve on there from a junk yard. You don't know what shape the car was in or if the part even works. If you're able to, find a buddy who's got one on his car and swap it out, his worked on his car so it should work on yours. No matter what you do you're probably going to have to spend money to get this fixed. Keep asking the questions like you're doing but don't spend alot of money replacing parts that are kinda off the wall. Alot of times it's as simple as a set of plugs and wires and if you're do for them anyways you're not hurting your car by putting them in there so long as they are good quality wires.
Doug

 

[84fiero4speed]

Thanks! Does anyone have any sugestions as to what brand of plug wires work best? Bosch are running $35 and Accel 8.5 are running around $45 at the local Autozone. Anyone have a personal preference?

 

[Doug99RS]

Bare minimum I would get a set from the dealer. If you don't get some from the dealer then I would get some of the performance wires that most of the turbo guys are running. I wouldn't trust most parts store plug wires for jack. I've seen alot of piss poor wires that don't snap on to the coil pack(s), won't clip on to the plugs, too long, too short, don't hold on to the valve cover and constantly raise up causing them to slip off the spark plugs. See what performance ones are being run and get those.
Doug

 

[84fiero4speed]

I think I'll stop by the dealer today and see what they have to offer. My friend said that the Accel 8.5s are a really good wire, that's what he runs in his car and he's been happy with them. Thanks guys, I'll get back to you later with the results.

 

[timmy]

NGK plugs and wires will solve your problem.

 

[99gst_racer]

Magnecor 8.5 wires are the best for a DSM. (in my opinion) They are rather expensive, but worth the money. What exactly does the EGR valve do and where is it located??

 

[AL92]

I have similar problems and this is what was done lately..checked electrical ..battery was bad replaced with red optima.alt ok.
Installed new air filer,fuel filter,pcv ,therm ,new accel wires and ngk plugs.Cleaned top end and bottom with CCC and engine flush,new sythetic oil.Took off cat and old catback to check for clogged cat and collapsed muffler.

Still exactly same.It starts good idles not bad but when you step on gas hard it just dogs and sputters and seems to backfire more and more and you step on it.turbo is boosting.

I am puttin in new o2 but really suspect from reading here and there that it is ignition coi.they are pricey too.IF not then then check fuel pump
and then other sensors but no check engine light.Car is embarrassingly slow be lucky to do a 20 second quartermile right now.

 

[timmy]

Anyone venting their BOV, if so some might argue that. that might be causeing it. I had the hks ssq and it fowoled my plungs.

 

[84fiero4speed]

Well I'm back, my computer has been in for repairs for the past few days and I just now got access to one so I could post back. My plug wires came in and I installed them. Everything seems to be fixed again, lets hope it lasts longer than last time. Of course the same day I fixed everything, a girl hit my car while it was parked and caused $1500 worth of damage to the front end. New hood, bumper cover, marker light, repainting.......just my luck I guess! Thanks for all the help, this site has saved my car yet again!