Minor engine studder at 3-4 lbs of boost (1 Viewer)

[Pierce]

I’m requesting wisdom. 1997 year model with supercharger. When I am cruising at 70-80 miles per hour and reach 3-4lbs of boost there is a minor intermittent studder. It only lasts a second and might only happen 2-3 times.
I’m wondering if anyone has some insight. It feels like a miss. I put a obd2 scanner on it and there is no variation in the TPS (but have a replacement if someone can convince me it’s the issue). I have a new coil just haven’t installed it. Only other thing I don’t have is a fuel pump but conventional wisdom says that they are bulletproof. Plugs, wires, cap and rotor were changed a year ago. I’ve wiggled the wiring loom near the egr and there is no change. Supercharger hoses are a year old.
Could there be something specifically supercharger related that I need to look at?

 

[SammyT96LX450]

I’m requesting wisdom. 1997 year model with supercharger. When I am cruising at 70-80 miles per hour and reach 3-4lbs of boost there is a minor intermittent studder. It only lasts a second and might only happen 2-3 times.
I’m wondering if anyone has some insight. It feels like a miss. I put a obd2 scanner on it and there is no variation in the TPS (but have a replacement if someone can convince me it’s the issue). I have a new coil just haven’t installed it. Only other thing I don’t have is a fuel pump but conventional wisdom says that they are bulletproof. Plugs, wires, cap and rotor were changed a year ago. I’ve wiggled the wiring loom near the egr and there is no change. Supercharger hoses are a year old.
Could there be something specifically supercharger related that I need to look at?

Colder plugs and get better wires. I had the same thing. My wires were as well only 1 year old.

 

[Pierce]

Oh, fuel filter changed 4ish month ago. This issue has been happening for 2-3 months. Could I have messed up the fuel filter replacement?

 

[Pierce]

They are toyota wires and they are the colder mr2 Toyota plugs.

 

[SammyT96LX450]

They are toyota wires and they are the colder mr2 Toyota plugs.

I used ngk plugs and wires and it went away

 

[Pierce]

Update... threw some parts at it... TPS installed and adjusted, coil installed, fusible link installed. Made sure none of the plug wires were touching using the roadkill zip tie method.

No change. Happens going up hill at 75ish mph under 3-4 lbs of boost. 2-3 little blips a few seconds apart.

Ordered some more spark plugs from wits end, thanks @NLXTACY for making this stuff easy to find.

Any other ideas while I’m waiting?

 

[Pin_Head]

No P030X code means no misfire, so what do you mean by “studder”?

It is tttttrying to tttalk ttto you?

 

[2fpower]

Try plug wires and plugs.

 

[scottryana]

Do you know what knock/detonation sounds or feels like? You are using 93 octane in your truck right?

 

[Pierce]

Yessir, running 93 octane. I’ve never experienced knock/detonation in real life. Listened to it on YouTube vids. Would it be fair to say it basically sounds like an old diesel?

No noises are associated with the studder. It’s just a momentary blip of power loss no longer than a second. No CEL, temps are usually around 180-185. It runs great except in those very specific conditions. I’ve owned it almost 3 years, it’s in excellent condition and have done tons of PM.

 

[2fpower]

Had several people comment on the same thing, my experience is that plugs and wires as fixed. Doing mine today.

 

[Pin_Head]

Ignition problems = misfiring.
No P030X codes, no misfires.

OP already changed plugs, wires etc with no change in the problem.

 

[SammyT96LX450]

Ignition problems = misfiring.
No P030X codes, no misfires.

OP already changed plugs, wires etc with no change in the problem.

I changed mine as well with Toyota oe and no change. Until I switched the wires and plugs. Trust me I went through all the steps as pierce did. This is what fixes the problem. Just like @2fpower stated.

 

[Pin_Head]

Maybe your was misfiring. Did you check?

 

[SammyT96LX450]

Maybe your was misfiring. Did you check?

No misfire.

 

[Pin_Head]

No misfire = no ignition wire/sparkplug problem.

More likely a lean mixture that isn't lean enough to misfire but lean enough to cause a noticeable power loss.

 

[Pierce]

For clarification my plugs and wires are about a year old. I now have a new set of each on order.

Last night i took it for a drive and as i was pulling away from a stop sign i had a series of misfires fot about 10 seconds that wouldn’t allow me to accelerate. Then the problem went away. The only thing i had messed with before that drive was plug wires.

Once i get the new plugs and wires installed I’ll report back.

 

[Pin_Head]

Does it get worse with more throttle? If so, it could be plug wires or spark plugs. Wires and plugs are not bad at only a partial throttle position; they are bad at a certain voltage and as the voltage increases with increasing throttle, they will still be bad. Check for a misfire code with an OBD-II reader. It can store a code, but not necessarily light up the CEL light if it is not encountered frequently enough.

 

[Pierce]

Yessir it got worse with throttle. I’ll check for stored codes.

I appreciate all the help guys.

 

[fj80rodngun]

Maybe a fuel delivery issue ie low pressure