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- From: wesf@boi.hp.com (Wes Fujii)
- Subject: EGR Experts Needed...
- Sender: news@boi.hp.com (News Server Project)
- Message-ID: <C0G2Gq.F4F@boi.hp.com>
- Date: Wed, 6 Jan 1993 18:10:02 GMT
- Organization: Hewlett-Packard / Boise, Idaho
- X-Newsreader: TIN [version 1.1.4 PL6]
- Lines: 50
-
-
- Okay, I'm over my head now. I'm trying to help someone else diagnose
- a lurching problem on an '86 Toyota Corolla. So far, the clues are:
-
- 4 cylinder, carbureted, 5-speed manual
- Lurching at steady state speeds, any gear
- Idles fine
- Has been tuned 3 times by 2 different shops
- New plugs, air filter, oil, oil filter, cap, rotor, no arcing at wires
- Carbon has been cleaned using the water-down-the-carburetor method
- 55K miles
- Ignition system is conventional (non-computer) advance with no knock
- sensor, no oxygen sensor
- Timing and spark look good and steady
-
- The engine seem to run fine with the EGR valve disabled (ie. hose
- unplugged) Checking the EGR vacuum line with a gage shows seemingly
- normal operation (no vacuum at idle or wide-open throttle). If
- I actuate the EGR valve with a hand pump, the engine behaves
- poorly.
-
- Questions:
-
- 1) Will I cause more severe problems letting them run the car with
- the EGR system disabled?
-
- 2) Without the EGR, are CO and hydrocarbons affected or is it just
- NOx that goes up?
-
- 3) Could it have a plugged catalytic converter which is forcing
- more exhuast back through the valve than the engine is carbureted
- for?
-
- 4) Could it be just a carburetor problem?
-
- EGR experts, what should I try next?
-
- Wes Fujii
- ________________________________________________________________
- ___ ___ ___
- / / / // /
- / /__/ // / A real motor is an Oldsmobile Rocket 455
- / HURST // / "This is NOT the new generation of Olds"
- / / / // /_______
- /__/ /__// // ___ \
- / // / \ \ Wes "BANZAI" Fujii
- / // /OLDS/ / Boise, Idaho
- / / \ \___/ / wesf@hpdmd48.boi.hp.com
- /__/ \_______/
-
-