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| 23 and 51 codes? | |
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| Tweet Topic Started: Sep 27 2012, 03:41 PM (727 Views) | |
| Econorodder | Sep 27 2012, 03:41 PM Post #1 |
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I purchased my 93 Metro, 1.0L, 5 Sp., 100K, a few years back and it served me well for about a year. I gave me about 48MPG most of the time. Then I lost 1, then 2 exhaust valves. I was lazy and took it to a shop to have the head reworked and when it came back, I was using about 1 quart of oil (5w20) per 100 miles, formerly it had used about a quart per 1000. 1700 miles later I was having terrible starting difficulties and did a compression check and I got 60,20,0. My valves were gone. After letting it sit for a couple years while I drove a 95 Metro that I had picked up, which never gave me better than 38MPG, I decided to tear down the 93. Upon pulling the head, I discovered all three "new" stock exhaust valves were burned and the headgasket oil drainback holes were the notorious tiny/out of place type. So I replaced the valves with stainless ones from Parts Dinosaur, enlarged the holes in the gasket and put it back together. I have about 500 miles on the repair. I'm getting good performance, reasonable mileage, virtually no oil consumption, but my problem is, the check engine light comes on every 50 to 80 miles and gives me either 23 and 51 or just 51 randomly. I've checked connections on the Intake Air Temp Sender(23) and it isn't loose (do they go bad?). I've also cleaned and sprayed the EGR valve(51) and the passages to some degree. Are these two codes linked in some mysterious way? I read of people getting codes if 5 or 10 miles, does it mean that my problem is only occasional, as the codes take so long to show? Any help is appreciated. Also could someone lead me to a good post on properly cleaning the EGR passages? Thank You. |
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| snowfish | Sep 27 2012, 04:31 PM Post #2 |
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Basic GearHead
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I knew I should have taken more pictures! Anyway, cleaning the EGR & ports is pretty straight forward. Spraying cleaner, into the ports, does little to nothing. They have to be reamed.![]() My picture shows the intake off, but that's not necessary. Remove the EGR. With the drill and low speed, and plenty of carb cleaner, you should be able to get all the way through to the exhaust manifold & intake. Rinse well and dry with compressed air. With the exhaust and intake valves closed, on cylinder 3, you'll hear air blowing into the exhaust pipe. You'll know that you've got all the way through the intake by the sound, of the compressed air, through the throttle body. For the EGR valve itself, just use carb cleaner & a brush. You may have to gently scrape the heavy stuff with a screw driver. Careful not to nick the shaft, though. Get a new gasket and you're done.I did this process, to my Wife's former 93, with no problems. Other than the car hating to swallow all the residual carb cleaner/liquified carbon. Smoothed out with a couple revs. For the temp sensor, I Did Not Test. I just through in a new one. Problem solved.
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| Econorodder | Sep 27 2012, 05:29 PM Post #3 |
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Thanks for the reply, that was very helpful. Is the temp sender you mention the intake air temp sender or is there one in the EGR system? |
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| snowfish | Sep 27 2012, 05:43 PM Post #4 |
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Basic GearHead
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Only temp sensor is on the throttle body. The one that can give us fits at times. Fan switch and gauge sender is by the thermostat. And Welcome to the Party!
Edited by snowfish, Sep 27 2012, 05:44 PM.
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Spraying cleaner, into the ports, does little to nothing. They have to be reamed.
Remove the EGR. With the drill and low speed, and plenty of carb cleaner, you should be able to get all the way through to the exhaust manifold & intake.
Careful not to nick the shaft, though.
Get a new gasket and you're done.
Smoothed out with a couple revs.
Fan switch and gauge sender is by the thermostat. And Welcome to the Party!
7:11 PM Jul 10