# Significant power loss.



## Damaioshin (Oct 5, 2007)

Recently, my 1998 Nissan Altima GLE has been running poorer than i'd like, and it isnt a gradual change, it happened overnight. It has 120,000 miles and never has had a problem before.

I am having significant power loss, esp. on the highway. Where normally it runs around 2.5k RPMs at 70mph, it now run at 3k. Not to mention accelerating to merge onto the interstate often redlines it. 

My service engine light is not on, so i have nothing to go off of there. I did an oil change, sparkplug and sparkplug wire replacement. None of which helped the problem. 

Any suggestions would greatly help, I drive over 1000 miles every 2 weeks on long interstate streches and cant afford to pay the gas while running at high RPMs like that.


----------



## stock98altima (Sep 30, 2007)

have you ever checked/adjusted your valve lash? mine just hit 132K and was loosing power, i noticed that the vlave cover gasket needed doing,so while i had it open i adjusted the valve lash with a feeler gauge. thats helped ALOT

also, have you checked your fuel filter/pump? whenever power goes down and RPMs go up always check the filter and maybe the pump.

now if only i could find out where the resistor block is.....


----------



## Ryan's Altima (Aug 29, 2006)

I know this sounds simple, but I had the same thing, and my air filter was caked with stuff, got a new one and now it accelerates perfect, I got 130,000 on mine. Probably 25k on the air filter.


----------



## Damaioshin (Oct 5, 2007)

thanks for your responses! But i dont know where the lalve lash is. I'm not that engine savvy...i know the basics, thats about it. 

And is there an easy way to see if my fuel pump is going bad?


----------



## stock98altima (Sep 30, 2007)

the valve lash adjustment would be on the lifters under the valve cover, the lash is basically the freeplay of the lifters on the valves.

if you can work a feeler gauge you can tackle this, but its good to have someone who knows what theyre doing around.

as for fuel pumps. just make sure its putting out spec PSI you can get little gauges to permenantly go inline under hood that will measure PSI. 

OR disconnect your fuel line from your filter(on firewall/bulkhead drivers side) , connect a length of hose and run it into the bucket, crank for a minute and measure output and do the math....


i owuld look into a guage, a little bit of plumbing f*ckin around and your set.


----------



## stock98altima (Sep 30, 2007)

the valve lash adjustment would be on the lifters under the valve cover, the lash is basically the freeplay of the lifters on the valves.

if you can work a feeler gauge you can tackle this, but its good to have someone who knows what theyre doing around.

as for fuel pumps. just make sure its putting out spec PSI you can get little gauges to permenantly go inline under hood that will measure PSI. 

OR disconnect your fuel line from your filter(on firewall/bulkhead drivers side) , connect a length of hose and run it into the bucket, crank for a minute and measure output and do the math....


i would look into a guage, a little bit of plumbing f*ckin around and your set.


----------



## jo31b (Oct 24, 2007)

Since your RPM is higher during the same speed, I'm guessing you have an Automatic Transmission.

I know you probably have, but don't forget to check the transmission oil level.

Here is the exert from the owners manual of how to do it to get an accurate reading:

TEMPERATURE CONDITIONS
FOR CHECKING ATF
c The fluid level should be checked using the HOT range on the dipstick after the following conditions have been met:
— The engine should be warmed up to operating temperature.
— The vehicle should be driven at least 5 minutes.
— The automatic transmission fluid should be warmed to between 122° and 176°F (50° to 80°C).
c The fluid can be checked at fluid temperatures of 86° to 122°F (30 to 50°C) using the COLD range on the dipstick, after the engine is warmed up and before driving. However, the fluid should be re-checked using the HOT range.
1. Park the vehicle on a level surface and set the parking brake.
2. Start the engine and then move the shift selector lever through each gear range.
Move the shift selector lever to P (Park) after you have moved it through all ranges.
3. Check the fluid level with the engine idling.
4. Remove the dipstick and wipe it clean with lint-free paper.
5. Reinsert the dipstick into the charging pipe as far as it will go.
6. Remove the dipstick and note the reading. If the level is at the low side of either range, add fluid through the charging pipe.
CAUTION
DO NOT OVERFILL.
USE ONLY NISSAN Matic ‘D’ (Continental U.S. and Alaska) or Genuine NISSAN Automatic Transmission Fluid (Canada). DexronTM III/MerconTM or equivalent may also be used. Outside the continental United States and Alaska contact an authorized NISSAN dealership for more information regarding suitable fluids, including recommended brand(s) of DexronTM III/MerconTM Automatic Transmission Fluid.
NOTE:
If the vehicle has been driven for a long time at high speeds, or in city traffic in hot weather, or if it is being used to pull a trailer, the accurate fluid level cannot be read. You should wait until the fluid has cooled down (about 30 minutes).

-------------------------------------------------------

Here is the PDF file location for Nissan owner's manuals if you don't have one.

Nissan Owners Manuals and Nissan Service Manuals

My suggestion probably isn't the answer but it's worth a try.


----------



## jserrano (Oct 27, 2004)

You are going to have to try an isolate the problem - which is easier said then done. But for shotgun approach, try spraying down the MAF sensor wire with some carb cleaner. And disconnect the exhaust downpipe to test whether you have an exhaust restriction somewhere.


----------

