Temp related fuel/starting issues?

[dodge]

Just replaced the fuel pump thinking that was the prob... Starts fine in morning...35-50f, but once the temp gets over 75f it just wont start. Am reading that FI relay may be the culprit? Thanks for any info anyone may have to pass along. This is a Mitsuba RZ-006 relay on a 93 Integra GS-R with 214K miles on it.

 

[djzachtyler]

if the issue presents itself at operating temps it is likely your 02 sensor. What exact year is your teg... on 90-91 there is a single wire o2 sensor that starts sending readings once the exhaust manifold reaches 300 degrees... it will continue sending while the car is still hot throwing off QA/F ratio and causing the car to no t want to start.

the 92-93 have a muliti wire o2 that "pre-heats" itself and send reading sooner, but can still result in what you are experiencing.

 

[dodge]

Well, have now replaced the FI main relay....and it still won't fire up. Turns over fine..battery in great shape and all the fuses in box under hood are good. Even those big 50A suckers. It finally quit starting even on the cooler mornings, so not sure what is going on here. HELP!! Where to next?? Oh, this is actually a 1992 model according to the info (1.7L etc) under the hood. A bad ECU possibly?

thanks so much!

 

[sportsma1539]

It could be the ecu. When you are experiencing this problem, is the c/e light staying on with the key turned over? Do you hear the fuel pump come on at all? If you had a fuel pressure gauge that would tell you if you were getting fuel at all. I had a similar problem and it ended up being the ecu . Depending on the specific symptoms it could also be the fuel pressure regulator.

 

[dodge]

Cracked the pressure side bolt on the filter(also cracked the other one as well separately after tightening the other)....no gas is coming out. Do not hear the pump come on either. Also, sprayed a little gas into the throttle body and cranked on it....didnt fire once. Assuming it is the ECU, is there any way to take it down to a local shop and have it tested? Where is the best place to get one if needed? Saw some on ebay for right at 200..

thanks!

 

[sportsma1539]

Hmm so what about the c/e light? Does it go off within 1-2 seconds of turning the key to the on position? If it doesnt, leave the key in the on position and leave the car sitting for about 10 minutes and see if it goes off. If it does i bet it will crank. I know you have changed both the fuel pump and relay but I would look up how to test them individually and confirm they are ok. It does sound like the ecu since you're not getting any fuel pressure and you have changed the pump and relay. Idk about testing the ecu. It will probably be hard to find a 92 gsr ecu. A b16 ecu might work. Probably want to look that one up because I'm just guessing on that one

 

[dodge]

Yeah, C/E light remains on past 10min...no start. Buddy checked it out this morning and we both think it most likely is the ECU. He is getting a good car..once the starting issue is resolved.

thanks for the help/info guys

 

[sportsma1539]

A b16 ecu will work. Very simple to change out. I'm thinking it will be a little easier to find one of those and maybe even a little cheaper than the b17. Once again I'm strictly guessing

 

[dodge]

Looks like there are places that will "rebuild" your ecu...around 200.00..may go that route.

 

[dodge]

ECU checked out OK at one of ECU rebuilders. So, have replaced the fuel pump, main relay..ECU is apparently OK..but no spark or fuel pressure. All fuses are good. Any ideas what could be the problem here?

thanks again guys

 

[1994 Integra]

Well if your check engine light remains on after 2 seconds of the key being on. You have a code or multiple ones. Tell us what they are.