92 multiple intermittent hesitations/stumbles while accelerating

[Wucko]

I am experiencing numerous hesitations or stumbles during acceleration. There is no noise or noticable RPM change assoicated with the hesitations/stumbles. Anyone have any ideas?

 

[FMExplorer]

Start with the easy stuff...
Have you checked spark plugs, fuel filter, air filter - stuff like that? Any chance the gas is bad? You could have a number of things going on - start with the easy ones. Also - please give the details of you rig in your signoff... year, model, mods, and so on...

JonM

 

[Goober]

Sounds like a good candidate for a MAS in need of cleaning/replacing(this is what mine was doing). Click on this link and see if this is what your experiencing. http://www.4x4central.com/tips.htm#mas if it doesn't help, it hasn't hurt. Then check plugs, wires,..etc..

 

[Wucko]

I changed the fuel filter and plugs about 3 months ago and I replaced the air filter two weeks ago. More information...the hesitation is not present until about 10 minutes of driving. Additionally, after cold starts the engine usually dies once.

 

[TPLYNCH]

In that case it could be the Idle Air Control or your Throttle Position Sensor going bad.

 

[tdavis]

try spark plugs..

try changing the spark plugs, esp. if they are bosch platinums. The bosch plat's have a tendency to blow the tip off the electrode.

You can always go buy cheap plugs to see if that's it.

 

[Rhett]

bosch plugs

I have never heard that about Bosch plugs...

Most people here seem to have Bosch Platinum +4's, which must be pretty good or so many wouldn't be using them.

But I am genuinely curious about your statement about Bosch plugs blowing their tips off...
please elaborate...

 

[tdavis]

I blew the tips off my bosch plats (not the the same as 4's). The truck would hesitate, and buck under full throttle acceleration. The place I took it the truck in for repairs put it on a scope, and said it had wierd things going on. They pulled the plugs, and replaced them with with a different set of platinum's. Problem solved.

They showed me the plugs. Let's see if I can represent it right here:

/-----\
| +---/
| | ^ <--- this had blown away.
| | | |
| +-+-+--+
| |

(ok, all attempts to format it correctly failed.)

Where the "this had blown away" points to, is a itty bitty little platinum dot on the Bosch Plat's. On 5 of the 6 plugs, it was *gone*.

Understand? So try different plugs.

 

[Rhett]

I would never put straight Bosch Plat's on my Explorer, anyway. Don't see too many regular Bosch Platinum's on trucks. On a car, maybe--but not a truck...

You either had improperly gapped plugs, the plugs were defective, or there is something else wrong with the wires or engine.