Originally Posted by Tony J
My '90 Accord 4 cylinder sometimes doesn't start. The problem occurs in hot weather when the car has sat in the sun, or the car has been run and let sit for 5 minutes or so. The remedy that has worked has been to try a few starts without gas, then a couple with mid pressure on gas and two starts with pedal floored - then I let the car sit for exactly two minutes and 90% of the time it starts on the first turn of the key. Sometimes I have to repeat this cycle more than once - rarely I have had to wait a few hours for the car to cool down.
I had the spark checked on one occasion and no spark was detected.
Last year I installed new igniter card and coil, but I have the same problem.
Could it be something to do with the sensors malfunctioning and the ignition system just not giving the signal to go?
Anyone have the same problem?
Does anyone know of a fix?
I just fixed this problem on my daughter's 90 Accord after many misses (chasing ignition).
To confirm problem is MAIN RELAY: While the car is refusing to start,
roll back carpet in trunk to reveal top of fuel pump/sender asm. Connect volt meter between YELLOW wire at connector and ground. Turn ignition to start. If voltage is present for about three seconds, relay is OK. If no voltage, confirm the diagnosis by applying 12V to yellow wire for a few seconds. Engine should start and run.
Failure seems to be on the relay circuit board, where solder connections gradually fracture and develop resistance. This resistance goes even higher when relay is hot from car sitting in sun. ECU then cannot tell when ignition has been turned to START and does not send requisite pulse of power to fuel pump. With no fuel pressure, car won't start.
Main relay is located under the cowl, attached under top of dash near the fuse block. Replacement part quotes ranged from 45 to 80 bucks, so shop around. The connector is a seven-pin block (row of four and row of three) with doubled-up wires on some pins. Look for a yellow wire at one end and black wires at the other end. I had to remove some bits to get access. Remove nut holding bracket and take relay out with bracket attached.
I was feeling frustrated from my earlier attempts to find and fix this problem. The fact that I prefer to work on cars in the cool of the day (when this problem never presents) may have been a factor. After $200 in ignition parts had not fixed anything, my daughter suggested I call Click and Clack about the problem. I laughed. Believe it or not, I was listening to their radio program while I was replacing this relay on her car (having diagnosed it with the test described here). A listener called about her car not starting on hot days. They asked if it was a Honda. No, she said, it was a '90 Acura. Without hesitation, they said replace the main relay; it was a well-known problem on Hondas (and Acuras) of that vintage. My daughter might have also suggested that I search the Internet, which I did not think to do until after I heard the call from the Car Show listener.