[4.3Lcougar]

well i finally got the baffles on the valve covers for the splitport 4.3L, but now it seems like the duration between shifts have become long winded. it was very responsive prior to the baffles and i dont think that its related at all to it, but what do you guys think.

it feels like a cross between lack of fuel and a tranny slip. the transmission is new and fluid level is normal. fuel pressure is at 20-22psi. i know that my o2 sensors are dirty from the oil blowing out the back and my rotor and cap are new! and sometimes feel like when your on the throttle and let completely off the pedal it decellerates faster then normal. i dont know where to even look. but i was going to clean the o2 sensors and pull the plugs to see it there nasty too. any other suggestions

thanks

 

[Porkchop]

sometimes feel like when your on the throttle and let completely off the pedal it decellerates faster then normal

that happened to me 3 years ago on my way to a meet...to make a long funny story short, it ended up being my maf...might want to clean it off? if not i dont know what to tell you, im too burned out from the engine swap

 

[master486]

That fuel pressure seems way too low. I don't know how you have your setup configured but stock is about 29-32 psi at idle and 39-41 psi with no vacuum.

 

[Porkchop]

yea now that i re-read that your pressure is kinda low man...you should have swapped in a 04 pi motor

 

[musto]

yea now that i re-read that your pressure is kinda low man...you should have swapped in a 04 pi motor

i had the same problem...

also, when i had it in park and reved it up, it was extremly slow and wouldnt rev past like 3k, and when i gave it gas it just bogged down unless the trans down shifted.


my fuel pump was bad, so i got a new one, and it helped a little bit, but the thing that made the biggest diffrence was the mass air flow sensor, i replaced that and then cranked it and noticed a diffrence right from the start. it revs fairly quickly now and when i give it gas it does what its soposed to.


i would definately recomend replacing the maf.

 

[4.3Lcougar]

well the MAF is new 73mm from SCP, i think ill clean the maf and raise the fuel pressure to 30psi. i agree the a pi swap might have been better but ive liked this swap so far, other then the issues here and there.... is there a special cleaner for mafs or is it just the same as a airintake/throttlebody cleaner????

i also noticed some backfires from the exhaust today.....huh!!!????

 

[musto]

well the MAF is new 73mm from SCP, i think ill clean the maf and raise the fuel pressure to 30psi. i agree the a pi swap might have been better but ive liked this swap so far, other then the issues here and there.... is there a special cleaner for mafs or is it just the same as a airintake/throttlebody cleaner????

i also noticed some backfires from the exhaust today.....huh!!!????

i belive the cleaner is the same, i dont think it matters too much.

 

[Porkchop]

just use throttlebody cleaner....carb cleaner will leave a residue

 

[master486]

Backfiring? Are you sure the timing is right? Because that could also cause your lack of power.

 

[Porkchop]

backfire? can we say timing is off?

 

[4.3Lcougar]

backfire? can we say timing is off?

i should have explained that a little better, when im driving and let off the gas, the rpms obviously go down, (deacceleration issue) and i'd get a occasional .....put put .....put....put.. like when you down shift... but i ended up cleaning the throttlebody and the maf, up'd the fuel pressure to 32-35 and put some fuel injector cleaner in the tank, and she seems to be back to her normal self... acceleration is definitely better and rpm's raise quicker instead on hanging out under 3000rpm. but i still have the put's from the exhaust... but other than that it seems to be good!

 

[Porkchop]

great!!!

now when are we gonna take some engine bay shots side by side

 

[4.3Lcougar]

great!!!

now when are we gonna take some engine bay shots side by side

what to see which one looks better...LOL i guess whenever we have another meet or you sell something to me where i have to pick it up......

 

[Thomas]

you're lucky you havent melted your pistons with that kind of fuel pressure. Get a freakin dyno tune man. You'll be surprised how many problems will disappear when you have a custom engine custom tuned.

 

[Porkchop]

yea its just 150 an hour for a dyno tune

 

[Thomas]

yea its just 150 an hour for a dyno tune

And how much does a melted piston cost? How much do you spend on an aftermarket part to get 6-10rwhp?

 

[racecougar]

Wow. I wouldn't drive my cars more than on/off the trailer without a dynotune. Do you at least have a wideband hooked up to it to monitor the A/F ratio?

-Rod

 

[4.3Lcougar]

who's got a trailer and where is there a dyno tuning palce in the central valley!!!!
obviously i am destroying my car by driving it.........

 

[Thomas]

well potentially yes. If you run it too lean you'll melt a piston. If you run it too rich you're just washing your cylinder walls and causing a lot of premature wear. Just want the best for your motor here. You'll get a lot more results from it with a dyno tune.
-Thomas

 

[rancherlee]

with the vacuum line off the fuel pressure regulator your fuel pressure MUST BE 40-42psi at idle, your computer won't be able to compensate enough if its off too much either way.