My friends 91 integra lS we have been dealing with a problem forever and i want to see if you guys agree or disagree… Ok here we go! we have the stock b18 in there, in the mornings or when he leaves the car sitting for a few hours, the car doesnt like to start as easy as it should. We found that one of the injectors o-rings are bad and it leaks, i told him that i beleive that it is that, that is causing the starting problem cause there is always pressure in the fuel rail so when you put your key into the ignition it is there to release the pressure and spray fuel onto the closed valves and once you start turning the motor over it releases that fuel into the motor, but if there is no pressure or not enough pressure it wont start until that pressure is built up in the fuel rail.
He is trying to find all these sorts of problems like valve adjustment, and something with the distributor, i keep telling him if it was something with timing or distributor you will feel it or hear it when the engine is running.
By the way when it does start there is no problem, minor popping in exhaust but definently needs a valve adjustment.
please help what can it be?
Well, most hard to start probs, whether cold or hot, are indicative of excess air, i.e. your injector o-ring prob. To test this theory when your bud stops in the morning, hook-up a spark tester to the #1 plug (easiest to see from drivers seat) and check for spark when he tries starting again. Good bright flash is optimum. Ipso facto and ergo:fuel leaks and gasket leaks. Most imes the main fuel relay would have cooled by then and started the car. This car sounds like it wants but can’t.
he has great spark we got new plugs and set the gap and everything but one thing that did get to me was that the old plugs were fuel burned, would the o-ring leaking cause the injectors to spray more fuel then programmed?
For about $6 a set I’d replace all the injector o-rings for starts. Then I’d do a cylinder leak down test to find out a couple things that would rule out low compression. One being slightly burnt valves. If all the oil drains away from your piston rings after setting for a while, then your not getting the right air/fuel mix at TDC compression at the right time(timing right on?). No, the injectors only spray a certain amount at the prescribed time, not variable amounts at start up.
:werd:
ok i get what you are saying, i am not sure but i think he did tell me there was a oil leak i am not sure though, we do have another head if it is something really bad and cant fix, we have replaced the cap and rotor, wires, plugs, and have o-rings that fit but are not vehicle spec and he just had an electrical problem with all his fuses blowing up on him for some reason unknowned but he blames me. what ever, but i want to fix this or atleast get the info to fix it. i believe he did say there was an oil leak, (not to sure if it is still leaking) his spark plugs are fuel burned. and he loses pressure in the fuel rail cause of the leaking o-ring. his gas miles have been noticably dropping. that is what some of the causes are. but as everyone knows once you start changing something on a car you need to be ready for the consequences.
Oil leak doesn’t stop a car, if you can keep lube in the pan. Those sensors went away with the advent of the ECU. Does this car have a hidden kill switch cause some mooron might have found it. Ha ha. But seriously, if theres other wiring slashed in there thats always a cause for a blown fuse. Otherwise, check out the MFR in the electrical section. What about the compression? Lube leakoff can significantly lower the ability to start right off. Heck, while your pouring over this dilema, check the igniter contacts.
the whole ignition has been replaced, everything except the tumbler and that works fine, we havent been able to do the compression test or hell get a chance to work on his car lately, he has a new girlfriend so for some reason working on his car is the last thing, taking her and friends every where is more important, but me if i was complaining about something with my car and we needed to get to the bottom of it i would be right there trying to fix it rather than driving everywhere possibly making the problem worse. No compression test the engine runs like a dream when it is started, but if the compression was off at all you would notice it when you pounce on the gas, not sure if any valves are bent, would you suggest that we just find a head gasket set and some head bolt and slap this spare refurbished head it has been ported and polished?
Perhaps “you” ought to keep his gf occupied for a change. 
But, seriously, a high performance head will just blow out an old bottom end faster. :read:
I also think your about a half hour away from diagnosing this problem as there’s only a couple other things to check. Keep tracking things down.
Okay so I have a similar problem but mine is it won’t start whenever the weather is hot like really hot outside, or when the engine is hot from running if I try to start her up minutes after shutting down it has hard time starting, usually I would run the fan to cool motor and wait like 5minutes. It was starting this way for a while, but then 2days ago like around noon it was close to 100 degrees outside and it would not start for nothing it would just crank and crank like it wants to start but nothing, so I try a few other times but nothing so I waited till later that day in the evening when it was cool outside like 78 degrees or so and it started right up without a problem, Now I know that its a fuel problem but im wondering is it a fuel filter problem which i have not changed in about 2yrs or so or Main Fuel Relay or Injectors leaking but it only happens in Hot weather and when motor is hot? Any ideas would be great I going to buy a fuel filter because I need to change it anyway, but if its hot out like that does it affect MFR also or no?
Try this, when you want to start the car, turn the key to run position, not start position, listen for fuel pump to sart and shut off. Do this twice, then try and start the car. If it starts, I think your filters old or the fuel pump pressure needs checked. Could also try this, before you try to sart open up the gas cap and allow the tank pressure to release, if it starts ok then check out the fuel rail pressure regulator, evaporative cannister and hoses for fuel return. Lastly, listen while in the run position for a buzzing noise from the relay under the dash (see Electrical section for details) that could point to a bad MFR which I think also controls the injector pack.
okay so I tried what you said and I heard fuel pump come on both times and car started up no problem, also the weather wasnt so hot but anyway also checked the MFR and it wasnt clicking or anything like that so tommorow I will replace the fuel filter and work from there since it needs to be changed anyway, Thanks for the tip