87 Civic Si 240,000miles.
Every once in a while my car decides it does not want to turn back on when I shut it off. It usually happens when I shut my car off in a drive thru, like today at an atm drive thru, took about 10 minutes before it would turn back on.
It will turn on, then idle really rough, then die. I watch rpm go down into nothing. Well today, I cranked and cranked until finally it started.

Also, the PGMFI comes on while I'm driving, has been since I've owned the car.

 

Check your alternator. I'm thinking your alternator is going bad. I bought a non running 86 SI. I had to swapped out the ecu,main relay, and fuel pump to get it running but it run like crap because of the PGMFI stay on so I changed out the alternator and the light went away. Now, it runs like a champ. Good luck.

 

i'm thinking you figure out what the code is. it isn't hard, the computer is under the passenger side seat. and you just have to see which LED's are on.

also, it sounds more like your fuel pump main relay is taking a dump. you can pull it out and re-solder the contacts.

 

My dad checked the computer lights and the only one that lit up was under number 1, which he said was the power light. He could be wrong but he is all I have to go by. So we are leaning more towards the problem being the fuel pump. Where is the fuel pump main relay located?

 

I really don't think it's the alternator. It was replaced in, I think, 07 when I first got the car.

 

The main relay is the little black or dark orange box with 8 wire plug into it, it's made by mitsubishi. It's above the main fuse box under steering wheel. I still think it's the main relay, fuel pump or the alternator.

 

Check your fuel filter too. I changed mine, it was dirty as hell, it made my car run like crap too, bogging.

 

there should be no lights lit up at any time unless there is a problem. there is no such thing as a "power light"

 

if it is indeed #1 then there is a problem with your 02 sensor

 

your cel light and your no start are two different issues.

No Start- ill put your left nut on the fact its the main relay. your car is 23 years old damn near and its tired. CHANGE IT!

CEL while cruising- if your old man was correct about code 1. your o2 sensor is to blame. replace and go cruising.

 

Okay, first off..no nuts.
I'll pick up an o2 sensor and a main relay next week. I bought a fuel filter last week and I'm about to put it in when the weather is nicer. I'm trying to get my car ready for long commutes by next year. Any other things I should look into?

 

Where is the o2 sensor located? and is there more than 1?
My car def decided it did not want to start at all today after class at the college.

 

Okay, well me and my mom went to check things out at the school... listen for the fuel pump, look for spark...
Well my battery was dead, so we hooked up the jumper cables just to see if it would turn on and mysteriously it did. It fired right up like it had no problem in the world. so I drove it around the parking lot for awhile and parked it in a tow accesible area. Going back to get it later... now why would it just turn on all of a sudden. This car is making me so mad. hahaha.

 

my friends 98 teg started doing this. turns out his battery cable was just corroded enough to mess with him..

 

That's funny that you said something about the batteries. I mentioned it to my dad and he tested the battery and stuff and said everything was good. He told me just to drive it until it started to act up again. So five minutes later, I go to discount auto parts to get stuff to clean battery cables, the battery lights starts flickering on at me. I pull into discount..I know my car is gonna die, shut it off, and try to start it back up..nothing.
Have them test the battery and alternator...and they are sooo dead. An hour and a half later, 2 blown fuses, the alternator came up bad....so its the alternator....the one thing i def did not think it would be. Does this normally do this to a car?

 

A bad battery can often destroy an alternator by overloading it. And a bad alternator can destroy a battery by under or overcharging it. Especially true if the battery and alternator are old. That's why it's important to keep your cables and connections clean and corrosion free all the time, you really limit the chances of a bad connection destroying something and then chain reacting to other components. The 10 minutes worth of work to disconnect and clean things up once in a while can save you a ton of money down the road.

 

Glad you fixed the problem. I had the same alternator problem before. I tried two alternator, both bad before the third alternator works. I even tried 1992 Civic alternator before the third alternator.

 

Well, my dad won't fix the alternator or replace the battery. Instead he bought a new terminal for it. It's weird, my car has been sitting in the same spot for the last 2 days, and the second he tries to start it..it starts. Especially since every day before school/work I will try to start it and it wont work. It's really ticking me off. How can the alternator and battery at discount auto test bad and not start at discount and test good for him at home..and start like nothing has ever happened? I'm def gonna take it to a shop when he says "its good to go" again.

 

I think the voltage regular for this car is in or part of the alternator. If the voltage regular is bad or going bad, it won't hold charged, battery drained. Keep trying.....

 

Haha. Well, his terminal idea didn't work so I went and bought a new battery. Didn't even get it out of the driveway before the battery light came on. So today, all of my savings to buy an alternator.

 

definitely sounds like the alternator. on the way home earlier this year in my 91 Si, i saw the charge light flicker, i pushed the clutch in to let the RPM's drop, light came on. i revved it back up released the clutch and above 3500 rpm it went off.. i knew immediately it was the alternator. replaced it the next day.. that was 20k miles ago.

 

Yea, new alternator can be expensive, maybe 70.00 and up at parts store. I'm lucky enough to be close to a junkyard here so I can get used parts very cheap; 3/4 dollars for a main relay, 16 dollars for an used alternator, and 10 dollars for a fuel pump....hehehe.

 

yeah. My dad used the alternator out of his project car....95 dx. but its running. very exciting! next is the valve cover gasket wooo.

 

and the veeeeeerrrrrry squeaky front end that no mechanic can seem to figure out...