the saddest day :(

[martina0917]

hey guys, it's terrible. my pathy was recently involved in a head on collision (wasn't that terrible) but since then i've been having all sort of problems. the damage was cosmetic but now i'm only getting 10 miles per gallon (from 20) when i brake it loses power and shuts down. when accelerating, it sputters, has no power and the rpm goes from 1K to 2.5K. also i can hear some backfire under the hood (driver's side). please help

 

so far, i've changed spark plugs and wires, fuel and air filter, cleaned the maf. fuel pressure is good too, so its not a fuel pump issue. but everything to no avail. thank you all for your time

[BoneZ]

hey guys, it's terrible. my pathy was recently involved in a head on collision (wasn't that terrible) but since then i've been having all sort of problems. the damage was cosmetic but now i'm only getting 10 miles per gallon (from 20) when i brake it loses power and shuts down. when accelerating, it sputters, has no power and the rpm goes from 1K to 2.5K. also i can hear some backfire under the hood (driver's side). please help

 

so far, i've changed spark plugs and wires, fuel and air filter, cleaned the maf. fuel pressure is good too, so its not a fuel pump issue. but everything to no avail. thank you all for your time

 

I would Suggest Taking a look at the tube between the air filter box and the throttle body, Having a rip in this tube can cause the erratic idle and power loss you are explaining. The problem with when braking it loosing power and shuts down I am not sure if related but they do die allot easier with this problem.

I found out about this problem when I blew apart my motor mounts while out 4x4ing and ripped that tube apart. Although We clamped the motor mounts back together then put the tube back together with spare rubber sheet and buck tape. I did see what a rip in the tube caused and it matches allot of you above statement.

[Nismojunky]

o2 sensor? been done to?

[Precise1]

Try the diagnostic proceedure to see if it says anything helpful.

http://www.nissanpathfinders.net/forum/index.php?showtopic=21

 

And look at the pinned topic in the garage to download a Factory Service Manual, it may contain some trouble shooting proceedures.

 

To search for vacuum leaks, let the motor idle and spray a flammable aerosol (wd-40, carb cleaner, etc) briefly and carefully at suspected lines and such. If the rpm increases briefly, there is a leak.

 

B

[martina0917]

thank you B. i'll take one of my wife's hair spray and run that check. i was trying to do the diag test yesterday, but couldnt. i'll try again today (need more practice).

 

also, i was reading more on this o2 sensor saying that if unplugged it will help in situations like this. where is the connection located under the hood. i found the connection to the exhaust but its difficult to follow the wires up. boneZ, the tube is intact.

[nige]

the o2 wire goes over the bellhousing, between the motor and firewall, and pops up under the hood, near the windshield on the passenger side. just unplug it and see if it runs better. Not sure how a minor accident would cause that part to fail, but you never know...

 

Does it stumble when the engine is cold, hot or both?

 

I agree with Precise1, it sounds more like a vacuum issue if the engine stumbles and dies when you step on the brake. Check all your rubber vacuum lines for damage, pinches or kinks. Check the brake booster vacuum line too.

[Precise1]

thank you B. i'll take one of my wife's hair spray and run that check.

 

You are welcome. I recommend something other than hair spray though, you don't want all your flex lines to be stiff, do you??

(a little should be ok though if you have nothing else)

 

B

[GrimGreg]

boneZ, the tube is intact.

Double check under the throttle body, mine split right behind the clamp on the bottom, you couldn't see it or feel it, but if you moved the tube you could feel the gap open up.

[martina0917]

hey guys. have an update for u geniuses

 

there is a problem with my brake booster. i need to change that (just waiting for the part now)

 

grimgreg u were right. i checked and double-checked and it was cracked. i had to disconnect it to check it properly. there's no where i can get one right now, but what i did was to tape it, then band it with a rubber tube.

 

finally, i found the o2 connector and unplugged it. Nige u're a good guide. it runs so much better. now, are there any negative impacts for having the o2 unplugged?

 

thanks as always

[Tungsten]

lower mpgs

[nige]

the o2 sensor plays a part of setting the air/fuel mixture when the engine has warmed up. Running rich increases carbon deposits and wears out the catalytic converter faster. Running lean increases the engine operating temperature. Neither are desirable so and get a new O2 sensor and install it. The usually last for 2-4 years before they fail. I like the OEM nissan sensor, but the bosch brand part is good as well.

 

Glad to hear you found the root of the problems. diagnosis is the hardest part.

[martina0917]

i'll try to get on ASAP. went to an auto parts location and they said that they'll order one for me. i cant afford lower MPGs, here in bze the cost per gallon is 10bucks (5USD)

[Precise1]

grimgreg u were right. i checked and double-checked and it was cracked. i had to disconnect it to check it properly. there's no where i can get one right now, but what i did was to tape it, then band it with a rubber tube.

 

Check in the Classifieds section here, there are several people parting out trucks and often people going to junkyards offering to get parts for people. Also post in the Parts Wanted section for the parts you want...

 

B

[BoneZ]

Double check under the throttle body, mine split right behind the clamp on the bottom, you couldn't see it or feel it, but if you moved the tube you could feel the gap open up.

 

Sorry I should have been more exact on where they brake, I have only seen them rip on the under side right at the throttle body or on the top right at the air box. I have went through more then one of these tubes now, Soon as the one i have on now goes I will be making a aluminum or brass version so I will not have the problem again.

That tube being ripped causes more problems then you can think of. also lets dirt and Darbee get in your engine. You will lose a vast amount of power, will get more ping, your idle will not stay at one place. That is just for starters. It will affect every vacuum system that has a line off that tube, you will be getting different air flow then you MAFs is reading so your ecu will correct off a improper air flow.