Jump to content

Cold start issues


Jhurkmans
 Share

Recommended Posts

So ive got a 1992 nissan pathfinder x3 v6 3.0l. I know that vehicles need to warm up in a cold start to run properly but this is strange. If it sits and gets cold and i try to run it the engine doesnt have any power. I can floor the pedal and the rpms stay between 500 and 750. It takes about 15 minutes to warm up and even then, until i get going its jittery; High rpms for a low speed on acceleration. After a cold start it barely moves and sometimes backfires. But after it gets going and is actually driving for about 20 minutes, it runs fine. Any suggestions? The timing is alittle off so it gets alittle higher rpms than usual and i havent had time to fix that but until seasons changed its been running okay. 

Link to comment
Share on other sites

Have you done a tune up recently? Could be a fouled plug or clogged (partially) fuel filter. Does it smell like it's running rich or lean when it's doing this?

Sent from my SM-G965U using Tapatalk

Link to comment
Share on other sites

Try checking the engine coolant temp sensor. It is the one with 2 wires. If it is blue, there is an updated one to help with cold temp/high altitude operation. The updated part is yellow (or is it the other way, can't recall). Either way, it is simply a variable resistor that changes with temperature to let the ECU know the temperature of the engine to control the air/fuel mix and ignition timing. If it is showing the wrong temperature, the engine won't be happy. 

Link to comment
Share on other sites

12 hours ago, Mr_Reverse said:

Try checking the engine coolant temp sensor. It is the one with 2 wires. If it is blue, there is an updated one to help with cold temp/high altitude operation. The updated part is yellow (or is it the other way, can't recall). Either way, it is simply a variable resistor that changes with temperature to let the ECU know the temperature of the engine to control the air/fuel mix and ignition timing. If it is showing the wrong temperature, the engine won't be happy. 

Thanks! So how do i check that? Im still learning about nissans, ive usually owned a chevy. 

Link to comment
Share on other sites

Thanks! So how do i check that? Im still learning about nissans, ive usually owned a chevy. 
Try unplugging it, the eco will go to a default value and if it runs better you can go from there

Sent from my SM-G965U using Tapatalk

Link to comment
Share on other sites

As with the GM, you can test the sensor by measuring the resistance at certain temps to confirm it is accurate. The service manuals give the details. I just know about the revised sensor because I live in northern Utah where my local elevation is about 4400 ft and I am in the bottom of the valley. It doesn't get particularly cold very often, usually doesn't drop below 10°F here. But I did come across the revision because it was in a TSB. When I bought my Pathfinder almost 21 years ago, I also bought an Alldata service manual for it. That included recalls and TSBs for the truck. The sensor was inexpensive and easy to replace, so I replaced it to prevent problems. Don't know if it had an effect, but haven't had any problems in 20 years related to that and that does include a lot of time spent over 7k ft and temps down to -35°F. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...