TRD/ Magnuson 4.0 Supercharger Tips, Tricks, and Mods

Time to get a non urd ecu get trd tune ditch the 7th injector and have justdsm do his magic.

 

Boy oh boy I looked into the seventh injector and I have no idea what in the fresh hell is going on there.

Curious what CAI you all are running. I don't think the URD true CAI I got is going to work for me. Fitment is off, but in ways that just aren't adjustable. Looking at an AFE box style, possibly an old school TRD if it can be found. And I'm guessing that's tough to find.

 

URD TCAI here. I had to modify/rebuild the bracket to push the filter away from the SC heat exchanger

 

Just stick with the stock intake for now. It’s not a restriction for a while and is already a CAI.

 

I would be interested to see a shot of how you did that - but the size of the filter is greater than the distance between the exchanger and the grill. It's pushing into both once I put the grill back on. Probably not worth the effort to modify.

 

Snorkel works great for me here in Az. Pulls cooler outside air, away from the engine bay, road, etc.. its also cleaner air. I have put my truck into limp mode when it was pulling from the fender while out wheeling. So much fine silt/dust gets kicked up right there at the pick-up, especially here in the desert.

 

Was that with the OEM inner fender liners? I guess I have the AFe Momentum Force intake and I have the pre filter installed for those occasional trips to the SW desert so I haven’t ever choked out this truck yet.

I never had issues with my 1st gen with many dusty/silty runs across Death Valley and other Nevada/Eastern Sierra trips.

 

Yeah, even with the liners in. I havent ran the liners since changing to the snorkel. Plus, 35s.. so everything is cut up/out anyways.

 

Hey Guys, I need your thoughts on an issue I have. If I give moderate load/acceleration to my truck when cold, the throttle becomes jumpy and erratic. When I come to a stop and idle, the truck will sputter and feel like it'll die. When the truck is fully warmed up, no issues and truck drives fine.

This started happening right after I switched from 3.0 to 2.8 pulley. I don't know if this is related.

• I've checked my air and vacuum line connections. No leaks. Sprayed brake cleaner with no idle change.
• No check engine light
• I pulled 3 of the spark plugs and they seem covered in a layer of black soot, although the tips were clean.

My current mods beyond the SC are:

• Exhaust cam gears
• AEM Intake
• AEM 320 fuel pump
• 2.8 pulley

OTT has tuned me for the above mods.

I'm stumped on what could only be affecting me while the engine is cold. Any ideas would be appreciated. Otherwise, I'm planning to go back to the 3.0 pulley and see if things go back to normal.

 

Clogged cats? Bad gas? Oil mixed with coolant anywhere? Low battery voltage?
Any misfires on scan tool (get a tool that tracks misfires). You might need to look at live data to decipher what makes it erratic when cold.

 

Usually I try to rule out things that it can’t be first, and go from there. That would include the pulley change. IMO, there is no way that could cause what you described.

I’m guessing you don’t have a wide-band otherwise you would have included that. So, best internet guess, I would suspect fouling misfires until things warm up. A number of things could cause this, a bad thermostat causing an overly rich condition leading to idle/low speed misfire is one of them. Another is simply bad plugs. Personally, I’ve had colder heat range iridium’s fail the same way (mine only had eight thousand miles on them).

I’m not a fan of a parts canon, but plugs are cheap and I’d probably start there until
you get some solid data telling you otherwise.

 

Thanks guys. I really appreciate your ideas and feedback.

Last night I removed my supercharger unit to replace the coolant temp sensor (at the back) and my spark plugs. Replaced with the NGK 2309 as recommended on page 1. I replaced the temp sensor just in case since it was cheap and plausible. I did install an AFR wideband, although after the cats.

It was a good reminder on what it takes to remove the unit and for me to double check conditions and connections.

JustDSM mentioned possible bad gas as well and something I'll need to wait for since my tank is full.

I'm running the truck today and I'll see how things go. Not ruling anything out just yet.

 

Something like what you described is usually pretty easy to figure out. I will say this though, take it step by step, and rule things out as you go. IMO, a number of things can be ruled out right away (as per your description of the issues and when it does/doesn’t happen).
First, it’s definitely not bad gas, because that wouldn’t go away once the engine is warm. This should be pretty self explanatory. Two, it’s not a clogged cat, because again, this wouldn’t go away (self explanatory again). Three, low battery voltage? Why would that change? The alternator supplies current needed once running. In 40 years I’ve never heard of one not working/then working, they usually just shit the bed and that’s that. Fourth, the pulley, the minute difference in size sure wouldn’t cause what you’re experiencing, if anything a lean condition under load (again, your AFR readings?).
The reason I mentioned the wide band is of course that it will tell you right away if a rich or lean condition is your cause.
In the end, something like this just takes a little old fashioned diagnosis, for example, the thermostat voltage should have been checked before changing.
I hope I didn’t insult, that’s not my intent. We all have common interest here and just trying to help.

 

I'll add- a scan tool could tell you more too. I wonder about an O2 sensor on the way out. Maybe not bad enough to throw the code but bad enough you're getting off readings when its still warming up causing the stutter.

 

Off topic.. kind of.

We got another order of NSX supercharger castings rolling through the shop. Been getting them set up today and updating programming, etc. Lots of finishing work on these..

 

Agreed. We can only help so much when it comes to internet diagnosing. You may have to do this old fashioned way and just check it out for yourself. However, what Billy mentioned tracks regarding bad gas, cats, and battery voltage.

You may want to consider changing our plugs if the soot you are mentioning is heavy enough and not just on the threads but deep inside the ceramic portion of the plugs.

As for me I would personally be looking more into PID data, specifically OCV or VVT solenoids and see how they are behaving during your issue. Get a log with as much pertinent info regarding throttle, coolant, MAF, and VVT duties. I'm probably leaving something off the table here but I think you understand where I'm going with this. I had a throttle issue for the longest time with my junk and it took forever to figure out, oh hold on, the OCV's can affect throttle input. Changed them out to some bullet solenoids years ago and haven't had a problem ever since.

That being said. The TAC of these trucks is the royal suck and I think outside of myself, my buddy and him alone is the only person who has ever been able to handle the way it behaves when slowly ramping in the gas pedal in order as to not burn out while taking off.

 

Thanks Everyone!

After driving yesterday with the new plugs, the problem seems fixed, for now. I tested under known issue-causing conditions and the issue is no longer present at idle. However, I'm still trying to understand what lead up to this.

When I pulled all of my plugs, they were all equally covered in a bunch of black soot. I had about 5K miles on the plugs.
Something I didn't mention was that I had been running without a re-tune since adding a new intake (AFE brand). I have an updated tune now, but had still experienced the issue with it and didn't think they could be linked.

I'm thinking with not having the retune + applying moderate throttle when the engine was cold, contributed to excessive build-up on the plugs.

 

I would not expect the intake to give you big problems unless you were going to a larger tube with different MAF which 100% needs new mapping/tune but a regular Tacoma spec intake should be able to go on without any big changes. These trucks can be gremlins. My trucks mpg tanked pretty bad recently and when swapping out my Tundra TB 76 for my bi annual CA apts I noticed my SC intake has a ton of grime in it. I have also been considering going back to the stock intake entirely as I have been having problems with silt getting into the engine from the TRD intakes. This likely is the filter (have since swapped to a stock 4runner paper filter). Def frustrating. The S/C could be exposing some problem you had on the truck before you put the S/C on as well.

 

I agree with your reasoning. I had been trying to think what only affected me when cold and not warmed up. I was trying not to get too worked up about it and go through the process of eval and reason.

I've never evaluated PID data before, but something to learn. Now that the truck runs better, it'd be prudent for me to know my current values.
If I full throttle from a stop, my tires will spin and hop, but it's pretty easy for me to accelerate without spinning since don't have as much power you have, haha.

Good point in the SC exposing an existing problem.
When I had removed the SC the other night, I noticed one of my vacuum lines pinched. Not completely, but almost. It looked to be the one of the lines going to the PWM vacuum switching valve. I fixed the kink. That and a slightly loose coolant hose were the only issues I saw.

 

Reverse engineering…. So the weather is finally good enough here to start on the truck again, and so it begins. Today I removed the 7th injector. Lots of plans for this spring, finally things are moving forward, it sure was a long hard winter.