Check Your Intake Tube!

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pcb

The Diagram Dude
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2002 MP5
I never bothered to check my intake tube because my car was running fine. I finally decided to check it just for the hell of it (I heard about the tube cracks about a year ago) and found two huge cracks going halfway around the tube. I taped it up for now while I order a new one.
After taping it, my Ultra-Gauge showed both my fuel trims went to between -13 and -23. After about half an hour my short term fuel trim returned to normal but my long term took 3 hours for the ECU to relearn everything.
I figured that a crack would have major driveability issues but that wasn't the case for me. I hate to think about how much dust, dirt and oily crap got sucked right into the engine.
 
^same thing on mine i found out recently...immediately jumped in 505's cold air box w/ piping GB (still spots open and he's shipping soon, get in it if interested)...

at first i was worried about 'dirty air'...but don't be...all of that will nearly immediately end up in the cat where it will be burned into nothingness, or in the oil filter...and as long as you've been frequent with oil changes, you probably did no damage at all...if the leak isn't big enough to effect ecu response (hesitation, codes, etc.) its definitely not letting even a small amount of unfiltered air in very often...
 
Im curious as to how cold intake boxes work? I mean i understand how a normal cold air intake works...but how does the box work?
 
^^What about particles of dirt scratching the cylinder walls?? The outside of the intake tube was covered in sticky black oily dirt and I know there was quite a bit of air leaking by the Ultra-Gauge's fuel trim dropping to -23 after sealing it up. (it would normally only drop to a max. of about -7).
 
pcb said:
^^What about particles of dirt scratching the cylinder walls?? The outside of the intake tube was covered in sticky black oily dirt and I know there was quite a bit of air leaking by the Ultra-Gauge's fuel trim dropping to -23 after sealing it up. (it would normally only drop to a max. of about -7).
Click to expand...

hence why i said check your intake tube in another post lol, as far as the sticky black oil, thats caused by the pressure from the valve cover which gets sent from a tube from the vc to the intake manifold, and i doubt any harm was done for the simple fact that how big can something be for it to fit through the cracks in your tube
 
Soundwave. said:
Im curious as to how cold intake boxes work? I mean i understand how a normal cold air intake works...but how does the box work?
Click to expand...

if you understand how a cold air intake works then you already understand 90% of how a cold air box works, picture a short ram intake now put a box over the filter that can resist/repel heat and then add a pipe/tube on the other side of the box that can draw "cooler" air from outside the engine bay or imagine the second pipe from your CAI that runs behind the splash shield attached to the box, tada you have a cold air box
 
Fresco said:
if you understand how a cold air intake works then you already understand 90% of how a cold air box works, picture a short ram intake now put a box over the filter that can resist/repel heat and then add a pipe/tube on the other side of the box that can draw "cooler" air from outside the engine bay or imagine the second pipe from your CAI that runs behind the splash shield attached to the box, tada you have a cold air box
Click to expand...

ah gotcha. thank you sir. Reps would be given if there was a rep system on here. lol
 
Fresco said:
hence why i said check your intake tube in another post lol,
Click to expand...

Yea, that's why I started this thread. I must have read "check your intake tube" a dozen times in the past year but never did. I was surprised that I had no symptoms.
 
pcb said:
^^What about particles of dirt scratching the cylinder walls?? The outside of the intake tube was covered in sticky black oily dirt and I know there was quite a bit of air leaking by the Ultra-Gauge's fuel trim dropping to -23 after sealing it up. (it would normally only drop to a max. of about -7).
Click to expand...
I replaced my intake tube late last year. I was inspecting something else and discovered it was cracked. The cracks were within the bellowed area, so hopefully, it was difficult for dirt to get in if the tubing in the bellowed area was squeezing the gap closed.
 
pcb said:
^^What about particles of dirt scratching the cylinder walls?? The outside of the intake tube was covered in sticky black oily dirt and I know there was quite a bit of air leaking by the Ultra-Gauge's fuel trim dropping to -23 after sealing it up. (it would normally only drop to a max. of about -7).
Click to expand...

Well the only way any internal part is going to get scratched is if there is airborne particles that are harder than iron and forged steel...i.e. silica (sand or glass)...which, yeah, can be found in dust...but its not like there are lbs of it just floating around everywhere you drive...and even then nearly every tolerance of the engine is designed to float on oil...and the oil is circulated under pressure...so it quickly washes foreign material away from those tolerances, where its filtered...

if you were driving on dirt roads all the time...its something to be more concerned about...but even then i'd bet with frequent oil changes, there was little damage done precisely because of the crack...in reality, a lot more s*** gets through the intake filter than what the manufacturers like to advertise...but its not really a huge deal imo...

I'm not saying drive around without a filter obviously...i'm just saying its pretty unlikely that you critically damaged your engine in any real way just by letting a little extra dirty air in there for a few months or whatever...For the most part the importance of an air filter stems from 2 stroke bikes, mowers, trimmers, etc...where as an air filter is absolutely critical because the lubricating castor oil is actually in the gas, where its mixed in the carb with air...and burned...dirty air makes the oil not do its job...at all...but a modern 4 stroke engine with its own dedicated and filtered oil supply...is pretty tolerant of dirty air...
 
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The odd thing is, I got my car oil sprayed today and the long term fuel trim shot up to +23 for the rest of the day but the short term fuel trim stayed around the 0 mark. I have no idea what that's about,... maybe some oil got on the maf or air filter (they hosed her down real good).

Update:
Well I checked my intake tube again and the electrical tape I put on it slipped off and left a gaping crack. Time for the all purpose extra wide, extra sticky duct tape. It doesn't look as nice but should work better. I'll place my order for a new tube today.
 
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with our protege coming to 10 year old, everyone should be replacing them even if they are not broken.... knowing that is common part that seem to only have 5-6 year life span....
 
Well I threw in some light bulbs and an oil pressure switch to help offset the shipping cost. A tube of silicone would be cheaper but I don't wanna be a cheap ass.

2002 MAZDA PROTEGE5 2.0L L4

Air Cleaner Intake Hose DORMAN Part # 696601 {#FP4713220A} CAD$24.14 1 CAD$24.14

Back Up Lamp Bulb WAGNER Part # 921 {#BP921} Miniature Lamp CAD$0.69 3 CAD$2.07

Parking Lamp Bulb GE Part # 1157NA {#1157NABP2} Standard Lamp CAD$0.83 3 CAD$2.49

Side Marker Light Bulb WAGNER Part # 168 {#BP168} Miniature Lamp Front CAD$0.30 2 CAD$0.60

Brake Light Bulb WAGNER Part # 7443 {#BP7443} Miniature Lamp CAD$0.96 3 CAD$2.88

*Oil Pressure Sender / Switch AIRTEX Part # PS123 * Oil Pressure Sender w/LIGHT - PROTEGE * * CAD$5.85 1 CAD$5.85*

Subtotal CAD$38.03
Discount -CAD$1.91

Shipping: Ground (FedEx or UPS) from United States
Shipping CAD$30.84
GST/HST (# 855114328) CAD$4.89


Total CAD$71.85
($70.84)
 
I got my new intake tube and installed it in four minutes flat. (although it was the third time I had it off).

My car is running awesome,... idles as smooth as glass,... I'm really appreciating that after hearing all the problems here on the forum.

I've got all my other new parts installed too (coils, plugs, wires, headlights (OEM), PCV valve, oil and filter, air filter) but I've still got my fuel filter to install (fuel pump housing).
I'm curious to see how much crap is in the filter media after 11 years when I break it open.
 
Here's a youtube How-To video for visual reference,... It's a 2000 Mazda protege 1.8 liter but our cars are almost exactly the same.

https://www.youtube.com/watch?v=9Som1GMsNs0

The part number he quotes for the intake tube in the video it the same as for our car. Dorman 696601
 
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So I go down to Napa to pick up the one and only 696610 intake hose they have in stock. Their part number is 610-3006 and they charged $6 more than their website lists. I get home and do a few things then head out to the garage to swap out the cracked hose. What's this? Seems about 3 inches too short. Parts jockey has the wrong part in the box although it looks very similar. It could only be better if Napa was closed now for the rest of the day.

(mad) And they are.
 
That one may by for a 1.6 liter engine. I saw one at a wrecker and like you said,... it was very similar but shorter. I took it to my car to compare before I realised it was shorter. He wanted $30 for that used one so I'm glad it didn't fit. That's too much money.
 
I did the electrical tape thing too while waiting on my new one. It slipped off into the crack and opened it right up. Then I redid it with duct tape it's stickier and wider and you can get it in black if you want to color coordinate things.
 
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