Help !! Major Loss If Power When Really Needed!!!

[KC2626]

Car - NISSAN PRIMERA SR20VE

Mods - K&N flat filter

Hi guys

When realy padel to the board (like u want to drag!!!) there is a major loss on power, it starts around 4000 RPM and go up to about 5500 rev and again form 7000 all the way up to 8000. can't find whats wrong ????????

But if gradually reve there is no problem at all, its smooth as ever

i am trying to change the plugs to see any progress but couldn't find any place to buy them... any one know a place to buy them (NGK PLFR6A-9 or NGK BKR6EIX-11)

Thanks

[The Don]

Yep some cars actually run better without the O2 sensor.. however I've seen with Nissans that the car sometimes may not start..

Machan on the topic of the Mirage's - what the deal with the two versions you see around the place? Are they any different from the 4 door ones?

he he yeah, I guess people came to be kind of aware about the O2 sensors thanks to the Nissans, I have heard of cars giving up on the middle of the road since the O2 sensor has failed.

Glad to say my humble ride is still running with one of the sensors having its wires knocked off which is still a mystery to me how it happened. And I guess since O2 sensors also play a part in emission control maybe the lack of one of a faulty sensor might result in a rich fuel mixture leading to more power

Pila do you mean the 2 door versions ? like the coupe's

My Coupe' which is a 1993 model is an ASTIZ grading and thus it came with a 4G91 engine as standard. Most Mirages come with either the 4G15 (1500CC) or the 4G13 engines to my knowledge, which includes a lot of the sedans.

or are you referring to the next generation of Mirages of which I think there are a few 4G92 Mivecs running arround. I think by default the Coupe's came with sportier engines than the sedans, though I might be wrong.

The Don

[sharkster]

he he yeah, I guess people came to be kind of aware about the O2 sensors thanks to the Nissans, I have heard of cars giving up on the middle of the road since the O2 sensor has failed.

Glad to say my humble ride is still running with one of the sensors having its wires knocked off which is still a mystery to me how it happened. And I guess since O2 sensors also play a part in emission control maybe the lack of one of a faulty sensor might result in a rich fuel mixture leading to more power

or u cud hav a lean mixture which wont b so nice

i havent really come across nissans knockin off cos of failed O2 sensors (tho u maybe rite)...all of the cases ive come across knock off cos of faulty crank sensors...one of the big reasons is engine washing...i never get my engine washd but jus manually cleand...service centres dnt cover everythng they'r supposd to prior to washin an engine

my uncle's N16 suddenly went dead in nittambuwa on his way to kandy...to his luck i was jus leavin work n wen he told me wat happnd i knew it was his crank sensor so we summond A*W all the way to nittambuwa carryin sensors...cost a bloody packet cos his cam sensor had knockd off too

[The Don]

or u cud hav a lean mixture which wont b so nice

i havent really come across nissans knockin off cos of failed O2 sensors (tho u maybe rite)...all of the cases ive come across knock off cos of faulty crank sensors...one of the big reasons is engine washing...i never get my engine washd but jus manually cleand...service centres dnt cover everythng they'r supposd to prior to washin an engine

my uncle's N16 suddenly went dead in nittambuwa on his way to kandy...to his luck i was jus leavin work n wen he told me wat happnd i knew it was his crank sensor so we summond A*W all the way to nittambuwa carryin sensors...cost a bloody packet cos his cam sensor had knockd off too

Hi,

Well considering the lack of knowledge amongst Sri Lankans about which sensor does what I might have been given the wrong information, and it might have been the cam sensor, though the story as passed up in which I am only a link (standard SL gossip) by the time it got to me the Cam sensor has turned into the O2 sensor ha ha ha. It was on FB15's I have heard of this happening though, and yes engine washing is what was sighted as the problem on all ocasions.

Incidentally Shaks this is just a theory ok, so I am inviting people to come forth and break it, but there is a thing as too much air being sucked in leading to a lean mixture.

I mean since the original problem discussed on this thread seems to have been solved by the owner reverting back to his OEM Air Filter, and the introduction of an after market filter seems to be related to the problem he had, could it be something like, since the after market filter allows for a greater and easier flow of air into the fuel injection system, and since the problem only manifested itself when it was revd up suddenly, and in gradual acceloration it seems to have no problems,

Could it be that the air flow sensor is malfunctioning, that it doesn't well enough to instruct the ECU of the sudden influx of fresh air over the usual levels expected so it could react by adjusting the fuel mixture ? and that by reintroducing the factory air filter all we have done is regulate the air flow within factory reccomended standards.

Just a thought, though even I believe it might have been most probably a clogged up after market filter that might have caused the problem by over oiling or something similar,

The Don

[Elvis_Pil]

he he yeah, I guess people came to be kind of aware about the O2 sensors thanks to the Nissans, I have heard of cars giving up on the middle of the road since the O2 sensor has failed.

Glad to say my humble ride is still running with one of the sensors having its wires knocked off which is still a mystery to me how it happened. And I guess since O2 sensors also play a part in emission control maybe the lack of one of a faulty sensor might result in a rich fuel mixture leading to more power

Pila do you mean the 2 door versions ? like the coupe's

My Coupe' which is a 1993 model is an ASTIZ grading and thus it came with a 4G91 engine as standard. Most Mirages come with either the 4G15 (1500CC) or the 4G13 engines to my knowledge, which includes a lot of the sedans.

or are you referring to the next generation of Mirages of which I think there are a few 4G92 Mivecs running arround. I think by default the Coupe's came with sportier engines than the sedans, though I might be wrong.

The Don

Yep I was actually asking if any of the two door coupes you see around the our roads have the 1600 MiVec engine in them? I have seen one Mirage hatch that has the Mivec scene in it.. The two door coupe in that case would be a very very good buy. thanks for the info..

machan out of curiosity how do cars run better without the O2 sensor? not sayin ur wrong cos i knw u ran witout it for a lil while correct? jus wonderin cos ur air/fuel ratio will be messed up witout it

I have noooo idea! But on my friend's city.. it actually did better on juice..

Yep Farzan there are a few known persons to remove their sensors and do a run or too.

[sharkster]

Hi,

Well considering the lack of knowledge amongst Sri Lankans about which sensor does what I might have been given the wrong information, and it might have been the cam sensor, though the story as passed up in which I am only a link (standard SL gossip) by the time it got to me the Cam sensor has turned into the O2 sensor ha ha ha. It was on FB15's I have heard of this happening though, and yes engine washing is what was sighted as the problem on all ocasions.

Incidentally Shaks this is just a theory ok, so I am inviting people to come forth and break it, but there is a thing as too much air being sucked in leading to a lean mixture.

I mean since the original problem discussed on this thread seems to have been solved by the owner reverting back to his OEM Air Filter, and the introduction of an after market filter seems to be related to the problem he had, could it be something like, since the after market filter allows for a greater and easier flow of air into the fuel injection system, and since the problem only manifested itself when it was revd up suddenly, and in gradual acceloration it seems to have no problems,

Could it be that the air flow sensor is malfunctioning, that it doesn't well enough to instruct the ECU of the sudden influx of fresh air over the usual levels expected so it could react by adjusting the fuel mixture ? and that by reintroducing the factory air filter all we have done is regulate the air flow within factory reccomended standards.

Just a thought, though even I believe it might have been most probably a clogged up after market filter that might have caused the problem by over oiling or something similar,

The Don

haha true the sensor wudve changd frm ear to ear...like u said standard SL goss

i think ur more or less rite...i think too much air cud hav been suckd in relativ to the quantity of fuel...maybe his injectors were cloggd and thus cud not pump enuf fuel for ignition...im not sure if he tried cleanin his injectors...assuming he did...yea maybe his airflow sensor is faulty n more air IS actually being suckd in...

but i think it was most probably a cloggd filter cos if aftermarket filters actually do force too much air in they wudnt sell...