84SE-EFI, Cats glow red, poor power...
11-01-02, 09:44 AM
#1
84SE-EGI helpy-helperton
Thread Starter
84SE-EFI, Cats glow red, poor power...
First off, thanks for all of your assistance with what I thought was a Fuel Injector problem over the past few weeks. Now that I've replaced the leaky injector, I now realize that the car is performing poorly due to SOMETHING ENTIRELY DIFFERENT!!
The car: 84GSL-SE, 13B-RE-EGI w/162k mi, stock 6 port induction, no exhaust mods other than PP muffler. K&N filter in stock housing, NGK BR8EQ-14's (new), new Dizzy Cap & Rotor. All emissions still in place - daily driver.
The problem: initially, the car had a leaky injector, but ran fine. I replaced the leaker and the car ran poorly, hunting idle, poor off-idle acceleration, and poor power, surging at steady-state freeway speeds - thought to be a bad injector. After replacing the injector last night with another rebuilt unit, the car runs the same, but noticed several other things:
* Cat glowing red hot after driving only about 4 miles (test drive after injector swap).
* still idles poorly, poor off-idle acceleration, poor gas mileage (200mi from 16gal tank, 12.5mi/gal), seems to be running on one rotor, lumpy and 'thumpy' sounding exhaust, slight backfiring.
After the test drive for the new injector, the Cat was so hot that it was cooking the oil in the drip pan under the middle of the car, and there's 5" of ground clearance here - it was REALLY hot.
Any suggestions appreciated, and thank you in advance, for taking the time to help me get this sorted out. This may still be an injector problem (out of spec, flowing too much fuel and running rich, causing Cat heat), but I'm leaning more toward something else.
Through search here, I have the SE fuel filter in hand, and will install tonight, but don't think this will fix the running rich problem. MAF? O2 Sensor? Something else? TIA,
The car: 84GSL-SE, 13B-RE-EGI w/162k mi, stock 6 port induction, no exhaust mods other than PP muffler. K&N filter in stock housing, NGK BR8EQ-14's (new), new Dizzy Cap & Rotor. All emissions still in place - daily driver.
The problem: initially, the car had a leaky injector, but ran fine. I replaced the leaker and the car ran poorly, hunting idle, poor off-idle acceleration, and poor power, surging at steady-state freeway speeds - thought to be a bad injector. After replacing the injector last night with another rebuilt unit, the car runs the same, but noticed several other things:
* Cat glowing red hot after driving only about 4 miles (test drive after injector swap).
* still idles poorly, poor off-idle acceleration, poor gas mileage (200mi from 16gal tank, 12.5mi/gal), seems to be running on one rotor, lumpy and 'thumpy' sounding exhaust, slight backfiring.
After the test drive for the new injector, the Cat was so hot that it was cooking the oil in the drip pan under the middle of the car, and there's 5" of ground clearance here - it was REALLY hot.
Any suggestions appreciated, and thank you in advance, for taking the time to help me get this sorted out. This may still be an injector problem (out of spec, flowing too much fuel and running rich, causing Cat heat), but I'm leaning more toward something else.
Through search here, I have the SE fuel filter in hand, and will install tonight, but don't think this will fix the running rich problem. MAF? O2 Sensor? Something else? TIA,
11-01-02, 11:35 AM
#2
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Either that you are running to rich and/or you have a clogged cat on your hands.
Side note: If you haven't replaced the 02 sensor before, this might be the time to do it.
-Error402
Side note: If you haven't replaced the 02 sensor before, this might be the time to do it.
-Error402
11-01-02, 11:39 AM
#3
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are you sure the leading and trailing ignition works?
maybe a crossed plug wire?
mike
maybe a crossed plug wire?
mike
11-01-02, 12:21 PM
#4
Rotary Enthusiast
Originally posted by error402
Either that you are running to rich and/or you have a clogged cat on your hands.
Side note: If you haven't replaced the 02 sensor before, this might be the time to do it.
-Error402
Either that you are running to rich and/or you have a clogged cat on your hands.
Side note: If you haven't replaced the 02 sensor before, this might be the time to do it.
-Error402
But my money is on the cat being clogged as well. Just remove the cat and go for a drive see how it feels.
11-01-02, 12:47 PM
#5
84SE-EGI helpy-helperton
Thread Starter
Getting spark, leading and trailing, no problem. In fact, this was one of the first things that I 'tuned-up' when the problems first started after replacing the leaking injector - new Cap and Rotor. Plug wires are routed correctly, checked and doublechecked. I used to run my 80LS in SCCA-CSP class, so I've done plugs a few times...
I would think that overly rich mixture would be putting unburned fuel into the cat, causing it to heat up excessively. A rich mixture would tend to lose power at higher RPM, but run smoothly up until then. I'm no expert at this, however.
Thanks for the assistance!
I would think that overly rich mixture would be putting unburned fuel into the cat, causing it to heat up excessively. A rich mixture would tend to lose power at higher RPM, but run smoothly up until then. I'm no expert at this, however.
Thanks for the assistance!
