96 2.3l hesitation? Almost stalls!

[Nitrodude]

Tried searching and can't seem to find a problem EXACTLY like this

I picked this truck up and it needed quite a bit of attention.

Firstly the cruise control cable held the throttle body open so it idled at 1500+rpm.
Fixed that, and made sure the tps was reading just below 0.99v fully closed.

Now, whenever you hit the throttle from an idle it'll hesitate. The idle drops down to almost stalling then it'll finally catch up and rev up.
It does this in park or in drive.


Now a little more background, just put in new plugs (old ones were blacker then black) did NOT do wires yet ( I'm broke LOL)
Did an oil change and cleaned throttle body.

Some other small issues with the truck...

The temperature gauge on the truck never seems to move. And the heat never really gets hot. My guess is a stuck open thermostat but I Havnt gotten around to checking it out.

Previous owner cut off the exhaust where the cat is and welded on an exhaust tip so it's ridiculously loud.

And lastly the speedometer was running off when I got it (seemed to run quite a bit faster then I was really going) and the other day it all together went out.


Just thought I'd share those last few problems in case anything was related!
Really want this hesitation fixed ASAP without dumping a ton of $ and guessing what will fix it.

Someone please help!

 

[Kowboy]

I'm thinking a timing issue could possibly be at least one of your issues. Happy hunting / Kowboy

 

[Nitrodude]

How would I check that?
Believe this engine is a timing belt/coils, so not adjustable?


What's weird is once it gets past the initial stumble it runs fine.
Seems to drive fine at higher speeds too-just not a whole lot of power (4 banger)

 

[Coolguy21]

timing belt

If i was you i would change the timing belt before it breaks.

 

[Coolguy21]

Or get a 3.0 v6 and drop it in for more power

 

[SRich]

I had several of the engine problems listed when I bought my truck (94 B2300). Have an auto parts store test your coils, run your engine in the dark and look for any ignition tracing, and have your ICM (little gray box mounted on the intake manifold) tested by parts store. You will be looking at about 60 per coil and 120 for the ICM.

 

[SRich]

Also try cleaning the mass airflow sensor and temp sensor in airbox.

 

[SRich]

Out of curiosity, is your tach indicating normally?

 

[Nitrodude]

If i was you i would change the timing belt before it breaks.

Only has 75k miles on the truck (still probably due because its from 96 most likely)

I had several of the engine problems listed when I bought my truck (94 B2300). Have an auto parts store test your coils, run your engine in the dark and look for any ignition tracing, and have your ICM (little gray box mounted on the intake manifold) tested by parts store. You will be looking at about 60 per coil and 120 for the ICM.

I've ran the truck in the dark-no sign of sparks.
Ill grab some maf cleaner and clean It and the iac.

Can any autozone check the icm/coils???

Out of curiosity, is your tach indicating normally?

Yup tach works perfect.

 

[Nitrodude]

Well rule out iac/maf.
Just ran to autozone and got maf cleaner and cleaned sprayed down both the maf and iac and reinstalled.
Started it up and same thing-hot the gas and the rpm drops down and it'll stumble a little then it'll shoot up to whatever you rev it to.

 

[wynnespeed]

my truck did the same thing (drop rpm then pick back up) turned out i unplugged my Mass airflow sensor and forgot to plug it back up the last time i took my air intake hose off. so if yours is plugged in and doing this, its probably bad. new ones like 50 bucks

 

[Nitrodude]

Is there a way to test this before I spend $50??

 

[SRich]

Autozone should be able to test the coils and the ICM. If not, call other parts stores and ask about your vehicle specifically. When I needed mine tested there was only one store in the town that had the correct test harness.

 

[Nitrodude]

Update.

After cleaning the maf and iac I drove it to the gas station and got $20 in fresh gas.
Not sure if its that or me driving it some but that initial hesitation seems to have gotten much better.

But a new problems arised-when the truck sits and gets "cold" when I start it up and start to initially drive-it acts like its running out of gas and comes very close to stalling but hasn't yet.
After it warms up a little it seems to go away.

 

[Nitrodude]

Almost forgot-my speedometer started working again as well (again pretty sure it's not correct-about 10mph too fast, but working!)