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I’ve got a (U.S.A.) 2002 OZ Rally Lancer that’s got 218K miles on it with several problems I’m trying to chase down. It’s got two codes on it that it’s had for quite a while but they’ve never affected the idle or performance before – P0402 and P0421 for the EGR and first catalytic converter. Mileage for combined city and highway for years has been reaching up to 32MPG until recently when a miss that usually occurred once shortly after the engine reaches full temperature has now become much more frequent. Also I’ve been experiencing very rough acceleration from a standing start even though I’ve cleaned out the throttle body (and there was a bunch of gunk in there). I usually manage that problem by gently accelerating till the butterfly valve in the throttle body is more open then I’m usually OK. A while back I did replace the O2 sensor on the first catalytic converter but I’ve not been able to dislodge the 2nd to replace it. Tried the special tool from AutoZone and then Channel Locks but had to quit before I tore a hole in the cat’s exhaust tube.
I’ve wondered about the Idle Control Valve. I pulled the original out and tried to clean it, couldn’t take it apart like the guy on YouTube because the stem was too far in so I couldn’t take the brown, twist lock cover off. This, apparently,seized the original one completely so I went and got another from the local junk yard. That one (from an 05 Lancer but physically identical) would actually retract about 1/16″ when you turned the ignition switch to “On” and did help a little with the idle problem originally but not now. How do you tell if that valve is actually working or not?
Today I discovered the purge solenoid valve for the vapor canister next to the EGR solenoid just below the intake manifold was the source of a regular clicking noise once the engine reached operating temperature. When I pulled the wires off of it the clicking stopped. Is this click normal? I don’t recall it doing this from times past. Could it be broken internally?
The actual EGR valve does work. I can put a little suction on it and it will all but shut down the engine if I keep it open a little. I’ve also replace its solenoid valve but I’ve never been able to detect any application of vacuum to the EGR valve while driving once operating temperature was reached. I put a T in the vacuum line to the EGR valve and ran a line from that to a gauge that I taped to the windshield. No vacuum was ever indicated once normal temperature was reached. I checked for kinks, too.
I also pulled the signal connections for each fuel injector on each cylinder to see if there was an RPM drop and there was. I think this produced an additional code I’d not seen before in the form of a misfire notice but only for one cylinder. I’ve cleared the codes to see if that one comes back. The others will I know for sure.
I have gone through and checked the plugs, cleaned and regapped them. The oil is still good as well as the air filter. The MAF sensor I cleaned a few months ago with the special MAF sensor cleaner. I’m pretty much at a loss as to where to go from here unless it’s that second O2 sensor that’s throwing everything off. The engine works very well up until it reaches operating temperature and then goes to pot, it seems. At 218K miles I’m worried about the timing belt who’s idler squeals like crazy quite often but that’s a huge amount of work or a $630 bill from my trusted mechanic in town. His time is certainly worth the money but I gotta have the money first!
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To fix the EGR problem, download the FSM and follow its diagnostic procedure.
The P0421 indicates a bad cat more likely than a bad O2 sensor. Since it’s so far just during warmup, it can wait till you start getting a P0420 or you have to go through emissions.
However, if fixing the EGR does not solve your acceleration problem, there’s a chance the cat is getting clogged. You can diagnose that with a manifold vacuum test.I did find a factory service manual for the Lancer with diagnostic tests described in it. Pulled the EGR valve itself out and it was pretty cruddy so I cleaned it out as best as I could. It’s possible a bit of carbon got caught under the valve seat and that did help a little.
There’s still a regular miss that I’m trying to locate the source of, though. I’ve checked the parameters for the coils and plug wires and they’re all within specs even though they may be originals. Don’t know as we bought the car used.
For a manifold vacuum test are you talking about just monitoring the intake vacuum to make sure it’s high enough?
Have you tried to spray some car cleaner on the intake plenums all around them to see if there is a vacuum leak it will idle higher when it sucks in the carb cleaner if it’s a vacuum leak could also be a bad idle air control valve I had to replace that on a couple of my vehicles egr could be taking a crap P0402 is exhaust gas recirculation flow excessive detected and P0421 is warm up catalyst efficiency bank 1 below threshold
Thanks Relative4 and Antonio. I’ll definitely try both.
After getting the car back together I got it warmed up and took it for a run. There is a regular, low intensity miss that holds the car back causing slow acceleration. I checked the resistance on the coils and plug wires and found they’re all in specs according to the shop manual but there could be an arcing somewhere as I think they’re original wires and coils. The plugs are only about 3 year old platinums. There’s no blue smoke coming out of the tail pipe so I don’t think it’s a lack of compression due to a bad cylinder.
When it warms up the vapor canister solenoid begins to click regularly. Put a vacuum on the bottom port and pulled a vacuum with a brake tool and it held. Top port evidently goes to the cannister. The solenoid coil checks good, too, according to the specs in the manual. Proper ohms. Is this clicking normal? I just don’t remember it doing that.
I performed the vacuum test and used carb cleaner around the intake manifold and any area that might have vacuum applied. No increase in rpm’s when the cleaner was sprayed anywhere.
The vacuum test had the car starting out around 16″ when cold then got to just over 19″ when fully warmed up. A gradual increase in rpms kept the vacuum fairly steady and began to approach, but never got to, 20″. Rapid acceleration dropped the vacuum down to about 15″ then it went back past idle vacuum by an inch-plus and then back to normal. Dropping from high rpm did get the vacuum up to almost 24″ or 25″ then back down to idle vacuum. I just didn’t see anything that looked abnormal according to the page you gave a link to above.
Clicking is definitely normal on older solenoids and that’s even goes for 4×4 solenoids they just get old the small miss your talking about sounds so much like a vacuum leak in the plenum let me know if you find anything with the carb cleaner does it fluctuate on idle any like if you just run it and watch the idle while it’s parked does it bounce on idle at all
I did try the carb cleaner, actually it was brake cleaner but it has the same effect, but could not get the rpm’s to run up regardless of where I sprayed it. A sticking EGR valve could be the problem. I did, however, fill the side of the valve that was dirty with what was left of my carb cleaner and it held the liquid until I moved the diaphragm and lifted the globe off the seat. Don’t think there’s much pressure on the exhaust side of the valve – unless it’s like Relative4 said it may have a cat that’s blocked up.
I’ll see if the code comes back. I’d cleared codes a few days ago but haven’t run the car enough to get them to come back.
The possibilities seem endless.
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