Lean at higher RPMs
10-29-2005, 01:18 AM
#1
1st Gear Member
Thread Starter
Join Date: Oct 2005
Location:
Posts: 100
Lean at higher RPMs
I have a feeling that just cleaning the MAF will help, but I want to get some outside opinions.
With a 95 5.0L HO, I have a specific way of duplicating the issue. It does do it in other situations.
In 2nd gear, (btw I have electric cut outs on my exhaust) with the exhaust cutouts open, at about 3500rpm, the engine will lean out given any amount of throttle, untill it goes into open loop mode. It will do it with the exhaust closed, but not as bad. With the exhaust open, it is so bad that at about 75% throttle it has 0 acceleration, and sputters awefull. But when it engauges into open loop it just rockets off.
Theory:
With the exhaust open it increases the flow rate of air through the engine a noticable amount at that RPM. Does not do anything like this at low RPMs, or at WOT. So, I believe that the MAF sensor is just not able to show the increased flow rate possibly because of dirt, or maybe I need to use a different one....I forget which vehicle this one is for. What do yall think?
Thanks in advance, and any input is appreciated!
With a 95 5.0L HO, I have a specific way of duplicating the issue. It does do it in other situations.
In 2nd gear, (btw I have electric cut outs on my exhaust) with the exhaust cutouts open, at about 3500rpm, the engine will lean out given any amount of throttle, untill it goes into open loop mode. It will do it with the exhaust closed, but not as bad. With the exhaust open, it is so bad that at about 75% throttle it has 0 acceleration, and sputters awefull. But when it engauges into open loop it just rockets off.
Theory:
With the exhaust open it increases the flow rate of air through the engine a noticable amount at that RPM. Does not do anything like this at low RPMs, or at WOT. So, I believe that the MAF sensor is just not able to show the increased flow rate possibly because of dirt, or maybe I need to use a different one....I forget which vehicle this one is for. What do yall think?
Thanks in advance, and any input is appreciated!
10-30-2005, 01:45 AM
#5
6th Gear Member
Join Date: Oct 2005
Location: st clair shores MI
Posts: 6,028
RE: Lean at higher RPMs
what plugs and plug gap do you have?
close them up to about .035 and see if it still does it.
if it does, you have a fuel pressure prob, if it doesn't, you have a spark issue
same thing for me about 10 yeras ago on a '90 GT....ended up being bosch platinums...switched them out and ran like a champ.
unfortunately, i chased demons for about a month and replaced the fuel pump, fp reg, coil, and some other crap b4 that
close them up to about .035 and see if it still does it.
if it does, you have a fuel pressure prob, if it doesn't, you have a spark issue
same thing for me about 10 yeras ago on a '90 GT....ended up being bosch platinums...switched them out and ran like a champ.
unfortunately, i chased demons for about a month and replaced the fuel pump, fp reg, coil, and some other crap b4 that
Thread
Thread Starter
Forum
Replies
Last Post
