mdash@sftri.UUCP (M.D.Scheer) (01/02/85)
Our trusty 1980 Accord has developed a nasty and puzzling bug. After ~30-40 minutes of highway driving (say 55 to 65 mph) it will start to lose power. Symptoms are characteristic of a fuel supply problem: dead low-to-midrange throttle, etc. The symptoms worsen if we continue driving and, after another 10 or 15 minutes, the car will stall outright. After sitting about 5 minutes though, we can drive off again, only to repeat the cycle. Two mechanics (at least one of which I have some faith in) have failed to find anything wrong with the car. The fuel pump is putting out good pressure; there is no physical evidence of fuel contamination, but the lines have been blown out and the fuel filter changed. They also replaced the air filter, checked the float levels, etc, and did some minor diddling of the CO adjustment. The ignition system appears healthy. These minor mechanical rituals are doubtlessly gratifying (and profitable) to the mechanics; only trouble is, they haven't fixed the problem. The car has 50k miles on it. Any net.honda-wizards out there?
prg@mgweed.UUCP (Phil Gunsul) (01/03/85)
[] One thing you didn't mention in your article is if you opened the gas cap. What I am thinking is that perhaps the vapor canister is plugged and you are creating a vacuum in gas tank. Phil Gunsul -- AT&T Consumer Products -- Montgomery Works
bhs@siemens.UUCP (01/03/85)
thislineistoprovethathtereisnolineeater,whichmustbeasyoucanreadthisright? Well, I have never owned a Honda, but there is an off the wall possibility that you have an exceptionally air tight gasoline tank. Perhaps the gas being sucked out of the tank is creating a vacuum, which the fuel pump is unable to overcome. How to check this? Next time you start losing power, and you are two or more people in the car, try pulling over with out letting the engine stall, and then have your passenger open the fuel cap shortly. You may hear a sudden hissing or rushing noise, and also, you may have restored engine power...but remember, you MAY, not you WILL. Bernard Schwab Siemens RTL Princeton, NJ
mlf@teddy.UUCP (Matt L. Fichtenbaum) (01/03/85)
In article <293@sftri.UUCP> mdash@sftri.UUCP (M.D.Scheer) writes: >Our trusty 1980 Accord has developed a nasty and puzzling bug. > >After ~30-40 minutes of highway driving (say 55 to 65 mph) it will start >to lose power. Symptoms are characteristic of a fuel supply problem: >dead low-to-midrange throttle, etc. The symptoms worsen if we continue >driving and, after another 10 or 15 minutes, the car will stall outright. >After sitting about 5 minutes though, we can drive off again, only to >repeat the cycle. I've heard of a similar-type problem on a car (not a Honda) in which the gas-cap vent hole was plugged. After prolonged driving, the gas tank built up negative pressure and the fuel pump couldn't supply the engine with fuel. Maybe you have a similar problem. -- Matt Fichtenbaum "Our job is to rescue fires, not put out your cat."
lincoln@eosp1.UUCP (Dick Lincoln) (01/04/85)
> Our trusty 1980 Accord has developed a nasty and puzzling bug. > After ~30-40 minutes of highway driving (say 55 to 65 mph) it will > start to lose power. Symptoms are characteristic of a fuel supply > problem: dead low-to-midrange throttle, etc. The symptoms worsen if > we continue driving and, after another 10 or 15 minutes, the car will > stall outright. After sitting about 5 minutes though, we can drive > off again, only to repeat the cycle. I'd like to add one perhaps remote possibility to the many gas cap/tank/line suggestions. Accords of this vintage have a crash protection fuel pump cut-off relay under the very left, lower side of the dash. The relay is a "one-shot, mono-stable mulitvibrator" type, and is fed by the same ignition low voltage pulses that drive the tachometer and by-passed by the starter buss on the ignition switch (powers the fuel pump directly). The cut-off relay failed on my '78 Accord in a bizarre way that somewhat resembled the symptoms above - the relay would become increasingly hot and sometimes would intermittently shut off the fuel pump. Eventually the gas feed would stop altogther. Sitting still for 15 minutes or so allowed the relay to cool down and start properly feeding the fuel pump electrons. Finally the relay quit altogether and I could diagnose the problem (out in the boondocks ). Fortunately I had a shop manual and some clip leads, so I fastened one to the fuel pump and the "parking light" drive in my trailor wiring harness and drove home with the parking lights on.
pwl@fluke.UUCP (Paul Lutt) (01/07/85)
I would just like to second the motion on the possibility of the fuel
pump cut-off relay acting up. I had a very similar problem with my
'78 Honda Civic which was fixed by replacement of the cut-off relay.
These relays are solid-state, i.e. transistor switching rather than
mechanical contacts. There are a pair of power transistors in parallel
driving the fuel pump. The failure seems to be due to one of the transistors
cutting out, leaving the remaining transistor to do all the work.
The symptoms are much like those described. First there is a loss of power,
followed by total stalling of the vehicle. Waiting a few minutes before
trying to re-start the car seems to temporarily get around the problem.
I have had other problems with the electronics in the Civic. The dash board
dimmer switch is also solid-state, using the same type of power transistor
to control the panel lights. I've had to replace this same transistor in
my dimmer in order to fix the thing. It appears to be a case of a Hi-tech,
low reliability system. Still cheaper than replacing an engine control
computer in a GM product (> $600). Hope this is of some help.
--
Paul Lutt (206) 356-5059
John Fluke Mfg. Co.
P.O. Box C9090
Everett, WA 98206
{allegra,decvax!microsof,ssc-vax,ucbvax!lbl-csam,uw-beaver}!fluke!pwl