Deck Plate and Power Loss?

[DSN46]

Apologies for posting two questions in one day, but the other post got me to thinking about this topic.

6 months ago, I did the Deck Plate Mod (4"). I put up a pictorial of what I did on my website. After running it open for about 2 months, I noticed that I really didn't have anymore "get up and go" than with it closed... so I closed it back up. Things were fine and she ran fine. I opened it up again last week just for grins (and to see if my first impression might have been wrong). Well, it's been a week (plenty of engine starts for the ECU to adjust) and it actually FEELS like it has less power than when the hole is closed! Is this possible? Is the whole "let the engine breath" thing just not right for our 3.4's?

Just wondering if anyone else feels like they wasted their time with this one.

Thanks,

James

By the way, MTL_4Runner, I'm hoping with your wonderful knowledge of the details of how our engines work you will respond!

[Lee]

i ran with the lid open on my airbox (ghetto / cheap deckplate mod :D) for about a week or 2 and i noticed no difference. what i did notice was a lot more noise and a throatier response and a dirtier filter :laugh:

imo, the noise alone gives people the impression it is giving more power, but i highly doubt it is. i also think there is no way it would give LESS power.

[neliconcept]

it can since its bringing in hotter air, to fix that, you need to build a sheild around the induction area so it brings more from the headlight instead of the engine bay.

I have build it using plexiglass and i noticed it actually helped gas mileage too.

[MTL_4runner]

The 3 key things you need to do are:
1) make sure you reset the ECU every time you open or close it (if power is your concern)
2) make sure your MAF sensor is clean (if not, hit it with some brake cleaner)
3) make sure you have a clean air filter

I don't really buy the air is hotter from the headlight than the fender unless your talking about stoplight to stoplight driving. Once you get on the highway you should notice a slight difference in passing power when you mash the pedal with the deckplate open than with the deckplate closed.

[DSN46]

Thanks again Guys!

1)I don't reset the ECU everytime. Every car I've owned adjusts itself after a certain number of starts (without unhooking the battery). Are Toyota ECU's not able to adjust themselves for the changing conditions over time? If this is crucial to do right when I get done with opening it, then let me know!

2) MAF Sensor is squeeky clean. I clean it every 6 months or so (just did it last month).

3) Air Filter is a brand new WIX installed last oil change (2 weeks ago).

I personally think there is something to the "hot air from the engine bay" thing. Spent years in the Heep world prior to coming over to Yota's. Open-Air filtration systems were also a hot topic of debate over on those boards. No one could come a consensus about the hot-ass engine bay air coming off that hot-running straight six (4.0) hurting performance or not. I know that I ran an open filter on two of mine, and noticed a loss in power until I did just what neliconcept did. I built a heat-sheild which allowed me to benefit from the added airflow. Then again, maybe I'm wrong... don't have a Dyno to test differences.... and the debate goes on.

I still would like know if the added airflow really makes a difference, so I guess I'll wait for more to chime in with their own experiences. Oh yeah, and "is immediately resetting the ECU crucuial?" Maybe I should try the heat-shield on this engine as well?
Maybe I should close the hole up with the cover and just make it a topic for discussion when I'm looking at my motor with my friends :D ... I don't know.

Thanks again everyone. I'll stop with the questions for a while now.

James

[MTL_4runner]

Every car I've owned adjusts itself after a certain number of starts (without unhooking the battery). Are Toyota ECU's not able to adjust themselves for the changing conditions over time? If this is crucial to do right when I get done with opening it, then let me know!


No, it will adjust like any computer controlled engine built today will, just resetting the ECU forces it to immediately relearn the new settings. If you're complaining that you're lacking power and haven't pulled the neg battery terminal to reset the ECU, try it.

So like I mentioned.....what situation are you saying you get less power?
Highway passing? Stoplight to stoplight? Grocery getting?

[reggie 00]

2) make sure your MAF sensor is clean (if not, hit it with some brake cleaner)


Aren't you actually supposed to use the Maf Cleaner?

Me and My Uncle, (who has forgotten more than i know about all autos) were talking about cleaning the MAF and i said carb cleaner or something similar, and he quickly shut that down said the only way to do it right with out damage was to use the MAF cleaner.

[MTL_4runner]

Aren't you actually supposed to use the Maf Cleaner?

Me and My Uncle, (who has forgotten more than i know about all autos) were talking about cleaning the MAF and i said carb cleaner or something similar, and he quickly shut that down said the only way to do it right with out damage was to use the MAF cleaner.


You can technically use either, but alot of the techs at the dealership use brake cleaner because it's cheap, plentiful and it works. Carb cleaner is a big no,no because unlike brake/MAF cleaner, it will leave a residue behind which can get baked on to the sensor wires when the MAF heats up during use. I don't know what specific chemicals are in each (Brake vs MAF cleaner), but I suspect there might be some overlapping between the two products (potentially the main difference could be just the marketed name). I know I have used brake cleaner many times successfully so there's no issue with using it as a substitute for "MAF cleaner".

[tacoclimber]

The deckplate mod for the Toyota 3.4 has been dyno proven to add at least 8 hp. However, that said, I agree that a dirty filter or MAF could cause a loss in hp. I guess the jury will always be out about the "hot air" issue...

[DSN46]

Okay, so I reset the ECU manually. After driving around for about 15 minutes, I took it out on the Highway. I could tell that there was more power when passing and in the 2000-2500 rpm range when getting up to speed. I think what I mean by power loss is that after driving it around for about 30 minutes (engine is fully hot), if I am driving in stop and go "city" type traffic, I feel like I'm putting my foot into an empty shell. I cant' really explain it. Foot presses hard on pedal, lots of engine noise, then no REAL appreciable gain in pickup... does that make sense?

I think it may actually boil down to the hot air being pulled from the engine bay. Don't know. Believe Im gonna try to fabricate a way to isolate the hole in the air box so it is sucking cooler air.

At any rate, I do appreciate the discussion. Thank you all for jumping in!
I'll just return to "James' Crazy Little World" over here and try not keep finding things to worry about. :roll:

Take care.

James

[MTL_4runner]

For stop and go city traffic, the hot air from the engine compartment might affect the performance, but shouldn't feel like your dragging a boat behind you. Up here, even though it can get hot in the summer my truck never feels very sluggish, but I've never had reason to put the deckplate in so I can't say what the difference might feel like (if there is any). Anyway if you come up with anything good for a baffle, be sure to do a writeup and post pics.

[DSN46]

Anyway if you come up with anything good for a baffle, be sure to do a writeup and post pics.


Will Do!

James