I have 3 codes preventing my 99 Protege from passing inspection

[angelfoodcakez]

I recently moved to Texas, and I got pulled over for my expired Florida plates. I have had them renewed, the stickers are just at my patent's place in Florida. Anyways, it's come time for me to pony up and buy the car from my folks and get the title transferred.

To get a title transfer, I need to pass inspection. It's a 99 1.6L Protege DX, with 106,000 miles on it.

When I took it to the inspection place, they pulled 3 codes from it. Apparently my "Check Engine" bulb burned out and has been "on" for a while, begging me to fix something. The three codes are:

PO171-System Too Lean
PO402-EGR Excessive
PO300-Random Misfire

The repair shop I usually go to tells me that I need the following work done to fix the codes:
PO171 - New air intake hose and mass airflow meter = $40 (air intake hose) + $136 (maf) + $86 (labor) = $262
PO402 - New EGR Valve, EGR VSV, clean EGR passages = $270 (egr) + $245 (labor) = $515
PO300 - New sparks and wires - $44 (sparks, wires) + $106 (labor) = $150
Check Engine Light - Rip out dash and put in new light - $172 (labor)
Labor is $86/hr at this shop

A little bit of history too: The air intake hose had a comically large gash in it a few months ago which caused the car to idle very roughly and stall out all the time. I fixed it with a liberal dose of duct tape and it's been running like a dream ever since. Could the 3 codes be linked to that? Could these be old codes that would go away if I simply replaced the air intake?

I already called Mazda, and it's way out of warranty, even for emissions stuff. I'm going to get a second quote somewhere else a little further out of town in a cheaper neighborhood, but I'm not sure how much lower they can go with all the work that needs to be done.

I'm thinking that with the right know-how, it shouldn't be extremely hard to fix these issues. I've already found the MAF, removed it and cleaned it. I've found a source for the air hose, so I'll replace that as well. The one repair I'm more hesitant about is the EGR stuff. The printout I got from the estimate says "EGR Valve, EGR VSV, clean EGR passages"

What all doers that entail?

[jewtewned]

ok here we go-p171-yes, replace air boot, the problem is probably gone since you cleaned it and taped up the gash, but the PCM still remembers.
The egr valve ports do need to be cleaned, they are common to be clogged with carbon and crap. But I've never had to replace an EGR valve, just clean the ports. As far as the random misfire, its possible the lean condition could have caused the random misfire, but does your car have a mechanical distributor, or just pure coil set up? I ask because those 1.6's had ignition coil problems for setting random misfire codes on Distributorless systems.
By the way, welcome to Texas!

[angelfoodcakez]

As far as knowing how to work on cars, this odyssey took me from 0-60 in no time flat. I got a ton of help online and from autozone.

What I ended up doing is just replacing the air intake and cleaning the MAF with MAF cleaner. I then cleared the codes at autozone and did a few hundred miles on 610 to get all the monitors in the ready state again. THe random misfire code was probably from when I ran out of gas the other week, but I replaced the sparks anyways because it was fun.

From what I read online, p0171 is almost always either a leak in the vacuum system (caused for me both by a gash in the air intake hose, and later by the hose for the cruise control becoming undone during other maintenance). The then p0402 was a code caused by all the unmetered air coming in from the leak, it didn't have much to do with the EGR in the first place.

Do you have any good information on getting to the EGR to clean it? I am wrenching for myself 100% now and am never going back to a mechanic if I can avoid it. The mechanic quoted me $1200, and I did it all for under $400. Over half of that was for tools and consumables I needed that I can use again in the future, and half of the tool cost came from the bluetooth OBD2 reader I got. Watching the catalyst system so from Not Read to Ready at 80mph on 610 was fun.

[jewtewned]

Bulletin No: 01-007/02

Last Issued: 2/25/2002
Subject:
MIL ILLUMINATES WITH DTC P0402 STORED IN MEMORY

BULLETIN NOTE This bulletin supersedes 01-012/01 issued 6/28/2001. The SRT (Suggested Repair Times) have been revised.

APPLICABLE MODEL(S)/VINs
All 1999-2001 Protege (1.6L)
All 1999-2000 Miata

DESCRIPTION

The Malfunction Indicator Lamp (MIL) may illuminate with Diagnostic Trouble Code (DTC) P0402 stored in memory. This may be caused by carbon deposits accumulating at the Exhaust Gas Recirculation (EGR) exhaust outlet port, inside the intake manifold. This may cause pressure to increase inside the exhaust gas flow circuit, resulting in stored DTC P0402.

Customers having this concern should have their vehicle repaired using the following procedure.

REPAIR PROCEDURE
1. Verify customer concern.

2. Confirm Freeze Frame Data was set for DTC P0402.

3. Remove Throttle Body according to Workshop Manual section 01-13.

4. Remove EGR valve (for Protege), or Surge tank (for Miata) according to the applicable Workshop Manual.

5. Using appropriate tool, remove carbon from EGR outlet port.

Caution: On Protege, DO NOT allow scraped-off carbon to fall into surge tank. Only allow carbon to exit through EGR port.


6. With compressed air, blow loosened carbon through EGR inlet port.

Warning: Wear eye protection (safety goggles) when removing carbon with compressed air.

7. Reassemble components in reverse order.

8. Verify repair.



WARRANTY INFORMATION
Note: This information applies to verified customer complaints on vehicles covered under normal warranty. Refer to the SRT microfiche for warranty term information.

[jewtewned]

I was trying to get a pic posted of what this talks about, but the damn thing wont work. Sorry, anyway I use usually a couple cans of carb or brake cleaner and the end of and old frayed speedometer cable. It takes a little time, especially if its really nasty. But the image I was trying to give you shows the intake after the throttle body is pulled off. There is a port in the center of the floor of the intake. This is where you spray in(you can also spray backwards through the EGR port) Just go back and forth, and if you have a cable or equivalant, start poking through and try to brake up the carbon. You should get to a point of when you spray in, you should start to feel the cleaner come through the other side. Good luck