Stuck with a no start condition.....again

Hi all, I own a 93 Integra and bought it with some issues. I have done a complete brake job and a lot of electrical work to the car. Yesterday, I was headed home and the car began to idle low. Like 100 rpms low. This has happened before but has remained intermittent, but then it died. I was running late so I tried to start it a few times and it came back to life, but then on my way home from work it did the same thing. My first thought was the possibility of off timing, but I doubt that is the issue as it is intermittent. My second thought was the fuel delivery system. It has low idle, could be the low fuel pressure and will occasionally die (maybe the fuel pump giving out). I’m sorry i don’t have much information other than this. I love the car, and work on cars all the time, but figured I would go here and maybe save myself some diagnosing times. The engine never runs rough the alternator tested good, as well as the battery. I plan to test compression later today. The idle issue does only occur when the engine is hot, after long trips (around an hour). Thanks for the help guys!

this response is no help but…

the fact that the issue only happens when the engine is hot is something i remember reading about some time ago. someone will chime in that knows whats up.

I sure hope so! I was thinking it could be the IAC or the FICV. I haven’t checked them, but the problem is only intermittent. I know they operate via vacuum, but the engine is fine when warm and i couldn’t find a vacuum leak, however i haven;t decided to pull out the smoke machine yet. Even then, I have noticed a vacuum leak will more than likely cause an erratic idle that will lead to stalling. I was thinking of the possibility of exhaust valves, as they get hot with the engine and that could cause poor compression. The likely hood, in my experience of just the exhaust valves going bad isn’t very likely. I appreciate your response, I did search but, had no luck.

[QUOTE=DA_all_day;2291074]this response is no help but…

the fact that the issue only happens when the engine is hot is something i remember reading about some time ago. someone will chime in that knows whats up.[/QUOTE]

here’s the chime in…

if this behavior is most prevalent when the motor is at operating temps I would suspect your o2 sensor… granted on the 92-93 integras you have a pre heated sensor… but anyways when these cars hit operating temps the A/F ratio gets misadjusted with a fouled o2… this can lead to low idle, overheating, and difficult starts when warm… ( car will seem to start and run fine cold until the o2 starts sending its fouled signal to the ECU)

2nd issue if your valves etc are good & clean ( IACV & FITV… Clean them out ) that can cause this is a failing distributor, or coil… first check the o2 sensor tho that is a easy 25 dollar fix. if that doesn’t help post back and we can keep on going :slight_smile:

Thanks for the insight! I have all data access, so testing these parts is easy, as i have the flow charts. I will check the 02. I have my ignition tester with me today, so I will run by the car and check ignition. If that’s not it, i also have my fuel pressure gauge. I have read, it may be as simple as a loose wire in the distributor, but like I said, I figured i would list symptoms here and I now have a direction for my diagnostics. Later this evening, or tomorrow, I will clean the IAC and FIT and probably end up changing the 02 sendor, as i habve an extra laying around :stuck_out_tongue:

sweet let us know what you come across :slight_smile: