SR cold start problem

[NY-240]

I did a search but couldn't find anything I hope you guys can help out an SR newbie here.The shop had just finished the swap so I went to check it out. When I cold start the engine, it will die out unless I keep my foot on the throttle for like 40 secs to a minute until it warms up than it'll idle just fine. I asked the guy who did the swap and he said the SR didn't come with a cold start feature or something and it's suppose to act like this??? I think they're jerking me and have no idea what they're talking about! Anyway, is it a commom problem with SRs or did they screw up something during the swap? like incorrect wiring, vaccum lines etc?? Pls help!

[S13240]

Mine is currently like that, but I'll be upgrading my stock ka fuel pump to the Walbro 255 hp fuel pump first to see if it solves the problem or it may just be my bov that is leaking because my bov does make a hissing sound when I turn on my engine.

[NY-240]

I already have a Walbro 255 in my tank so I don't think it has anything to do with my start-up problem. Anyone else experiencing a similar problem with their SRs?

[chrispy]

someone on here had a problem like that awhile ago.

[ItzGenX]

Is your check engine light on? Your O2 messed up? Thermostat? Ok, lets go over the "Four-Stroke 101". When an engine is started cold, it needs to run rich in order to keep going. Many cars use the water temperature to know to run rich or not. Many times, when a thermo or temp sensor is messed up, they either keep telling the engine is warm all the time which leads to poor cold starts, or they are telling the engine that its cold all the time and leads to high idles and very rich mixtures. The O2 plays a role in this also by "testing" the air mixture of the exhaust gas to determine if its lean or rich and tells the computer to add or take gas to the mixture compared to the condition the engine is in. Those are the main culprits of a rough cold start in most cases. Go check those out.

-GenX

[NY-240]

Thanks alot for your input ItzGenX. I'll look into these areas! One thing I forgot to mention is I have an Autometer A/F gauge installed but it recieves no signal during cold start (that bouncing light didn't go on at all). Does it mean the 02 sensor is not functioning properly?

[chrispy]

http://www.nissaninfiniticlub....start

there you go man. I knew we talked about this before. There is alot of replies to this one too.

[ItzGenX]

Those A/F things do more good then harm in my records of seeing them installed. I've seen 3 fried ECU's, 1 dead O2 sensor, and twice they could never figure out what was wrong after they installed the A/F meter. Car would not run right, stay rich, and even after uninstalling the A/F meter, it would still be a rich burn. Then those things aren't as accurate as you would think they are to begin with. Its all for show. The meter could have damaged your O2.

[NY-240]

Thanks alot chrispy, that's a very informative thread! Here's my run-down of all the potencial problem areas:

-02 sensor-ground wire-dirty MAF-fuel filter

I'll post here again as soon as I find out what causes this so the next person encouters the same problem will know what to do. Thanks again!

[NY-240]

Those A/F things do more good then harm in my records of seeing them installed. I've seen 3 fried ECU's, 1 dead O2 sensor, and twice they could never figure out what was wrong after they installed the A/F meter. Car would not run right, stay rich, and even after uninstalling the A/F meter, it would still be a rich burn. Then those things aren't as accurate as you would think they are to begin with. Its all for show. The meter could have damaged your O2.

You might be right since the A/F is tapped right into the 02 sensor and as I mension earier the meter shows nothing during the cold-start. If that's the case should I hold the shop liable for the damage and demand a replacement sensor from them?

[ItzGenX]

You can give it a try, but I doubt they will replace the O2. See, this problem exists with MANY A/F meter installs. It's very common indeed that most people who install it either don't give a damn anymore or just never was aware that the problem existed. Through all my experiences and watching people in person have problems with it, I have never seen a clean working install with no side effects. First figure the problem out exactly before anything. Sounds like your O2 because no real signal goes through during a cold start, but dont jump to conclusions. O2 sensors are made to work at certain temperatures, so maybe the O2 is in fact good. I would check into the thermo and temp gauge sensor first.