:help hey.. my first post on here... been reading a while but not much said. ok. when my car is cold i.e. just started or sitting all day. it hauls bootsy. when it warms up, no more bootsy. I have searched all day here and at zilvia.net. no luck
is this a timing problem?( i know timing is advanced during warmup.) a air fuel ratio problem.. or something i have no clue about. ive only had my 240 a while.. and I love it to death. I dont want to lose faith... any input is appreciated..
fast when cold/slow when hot
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punkblackS14
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96_S14_SE
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- Car: 96 S14 SE - 05 VW GTI 1.8t - 89 S13 coupe "gold on brown"
Advanced, and because hot air is less dense is why its slower generally.
When you crank the car up the engine bay, TB, intake runners, and head are all cold. So the air comes in without really being warmed at all prior to entering the combustion chamber. Cooler air is more dense thus has more oxygen, thus allows for more fuel, which creates more power
Upon warming up the engine bay heatsoaks from radiated heat from the cooling sytem, the exhaust sytem and the block itself. Im guessing your intake sucks air in from the engine bay, and this is where it starts.
The hotter the underhood temps the hotter the air one starts with. From there it goes to the throttle body witch has HOT coolant running through it (well not on mine hehe), and it heats the air.
Note if you have a metal intake pipe that isnt thermally wrapped the air is also heated along this intire peice as well, due to heat soak of the metal.
Then you pull air through the runners which heat soak, as aluminum is a great heat conductor, from the underhood temps, head (which heak soaks from combustion), coolant passageway cast onto the side, and so on. Then it gets to pass through the head and over the nicely warmed intake valves...
There is also the egr sucking hot fumes into the mix from 2k - 4k, if your car is still so equipped
Um yeah thats why... If it goes from decent to dog slow then I would be a little concerned. But im not to versed in terms of bootsy so I dont realy no how extreame of a performance hit that is.
When you crank the car up the engine bay, TB, intake runners, and head are all cold. So the air comes in without really being warmed at all prior to entering the combustion chamber. Cooler air is more dense thus has more oxygen, thus allows for more fuel, which creates more power
Upon warming up the engine bay heatsoaks from radiated heat from the cooling sytem, the exhaust sytem and the block itself. Im guessing your intake sucks air in from the engine bay, and this is where it starts.
The hotter the underhood temps the hotter the air one starts with. From there it goes to the throttle body witch has HOT coolant running through it (well not on mine hehe), and it heats the air.
Note if you have a metal intake pipe that isnt thermally wrapped the air is also heated along this intire peice as well, due to heat soak of the metal.
Then you pull air through the runners which heat soak, as aluminum is a great heat conductor, from the underhood temps, head (which heak soaks from combustion), coolant passageway cast onto the side, and so on. Then it gets to pass through the head and over the nicely warmed intake valves...
There is also the egr sucking hot fumes into the mix from 2k - 4k, if your car is still so equipped
Um yeah thats why... If it goes from decent to dog slow then I would be a little concerned. But im not to versed in terms of bootsy so I dont realy no how extreame of a performance hit that is.
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punkblackS14
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punkblackS14
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96_S14_SE
- Posts: 973
- Joined: Wed Nov 06, 2002 11:10 am
- Car: 96 S14 SE - 05 VW GTI 1.8t - 89 S13 coupe "gold on brown"
No aiv hehe nissan realized they where junk and took them out.
Egr is a yes, as well as the evap canister. EGR is located in the back side (pressed against the firewall) of the intake manifold. While removing it is the best thing, I just disabled mine by disconnecting then plugging (those little press in inserts used to hold shelves up work nice hehe) the vaccume hose going to the egr valve. With out vaccume the thing cant open hense no recirculated exhaust gasses. Only down side is the egr pipe still gets hot and will add to the intake mani heat slightly still.
If you want to remove the evap it is either in one of two areas pre mid model year 95s or obd1 will have them in the engine bay's frontal area (cant rem precisely where, front left iirc), while the obdII (mid model 95 -98) they are located where the diff oil cooler would be if this wasnt america.... Oh wait I mean in the rear of the car, underneath, on the passenger side. Just got toward the rear of the rear pass tire, under the car and look up. Its a big black box with 90000 hoses on it hehe.
Um tampering with ECD's is baaaad. hehe just thought I would throw that out.
Egr is a yes, as well as the evap canister. EGR is located in the back side (pressed against the firewall) of the intake manifold. While removing it is the best thing, I just disabled mine by disconnecting then plugging (those little press in inserts used to hold shelves up work nice hehe) the vaccume hose going to the egr valve. With out vaccume the thing cant open hense no recirculated exhaust gasses. Only down side is the egr pipe still gets hot and will add to the intake mani heat slightly still.
If you want to remove the evap it is either in one of two areas pre mid model year 95s or obd1 will have them in the engine bay's frontal area (cant rem precisely where, front left iirc), while the obdII (mid model 95 -98) they are located where the diff oil cooler would be if this wasnt america.... Oh wait I mean in the rear of the car, underneath, on the passenger side. Just got toward the rear of the rear pass tire, under the car and look up. Its a big black box with 90000 hoses on it hehe.
Um tampering with ECD's is baaaad. hehe just thought I would throw that out.
Any luck with the problem Im having the same problem, i already try disabling the EGR no luck the car ran a bit richer, the AIV i took it oof completely and the car runs the same, changed fuel filter, new intake, changed wires and plugs and well the 02 sensor as well, i just performed a self diagnostic test on the ECU and i got no code which according to the instructions in the FAQ site means no problem. But yes there is a problem the car when cold is pretty fast even chirps second gear when hot, is really slow, considering the fact that hot air is less dense. A nissan Altima completely stock and Auto beat me by cars. The only weird thing i've noticed is that there is a water line running horizontally in between the intake manifold and the head that every time that i fill the reservoir it spills it all out through a lil tiny hole it has, once it leaks it id stops leaking, doesn't any more water leak through there? Please help me out i really don't know what else im going to do, and i really don't want to take it to a mechanic. thank you for your help.
In addtion to less dense air:
When teh ECXU sees teh coolant temp above a cetratyin level it retards timing+ lowers power.When it rises a few more degress = more retardation and more powerloss.
In most cars tha6t suffer lots of powerloss in summer this is the cause.
recommendation new radiator, and just in case new tstat and waterpumpm too. 1-888-209-7942 is the number for Jayson at nissanwholesale parts a NICO member give sout real good discounts for NICO members too.
Anotehr phenomenon that can cause great powerloss in summer is "summer knock" which if caught by the Knock sensors will also make the ECU dial back the power.
Soltuion fir this problem: ( clean out combustion chamber.)
Add seafoam or MMO to your gas and drive it real fast ( on a cool nite) so u dont have summer knock.
Most l;ikely too high a coolant temp though.
This may be the case even if your gauge doesnt say so.
Fred...
When teh ECXU sees teh coolant temp above a cetratyin level it retards timing+ lowers power.When it rises a few more degress = more retardation and more powerloss.
In most cars tha6t suffer lots of powerloss in summer this is the cause.
recommendation new radiator, and just in case new tstat and waterpumpm too. 1-888-209-7942 is the number for Jayson at nissanwholesale parts a NICO member give sout real good discounts for NICO members too.
Anotehr phenomenon that can cause great powerloss in summer is "summer knock" which if caught by the Knock sensors will also make the ECU dial back the power.
Soltuion fir this problem: ( clean out combustion chamber.)
Add seafoam or MMO to your gas and drive it real fast ( on a cool nite) so u dont have summer knock.
Most l;ikely too high a coolant temp though.
This may be the case even if your gauge doesnt say so.
Fred...
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sil80drifter
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