New to this so bare with me. I race a 88 Sentra/coupe in what we call Bump-n-Run in Montana (It,s a combination offroad racing & demo derby). My problem is at idle and at rpm's lower than 4000 it runs great, over that it starts tearin up and turns new spark plugs black in just a few minutes. I've changed plugs,wires,cap,rotor,all filters,vaccuum lines,coil, and doesn't change. I would like to be able to run codes on it but the car is totally stripped out so I don't have any flashing lights to count. I hope someone can help me out racing season is about here.
New to this so bare with me. I race a 88 Sentra/coupe in what we call Bump-n-Run in Montana (It,s a combination offroad racing & demo derby). My problem is at idle and at rpm's lower than 4000 it runs great, over that it starts tearin up and turns new spark plugs black in just a few minutes. I've changed plugs,wires,cap,rotor,all filters,vaccuum lines,coil, and doesn't change. I would like to be able to run codes on it but the car is totally stripped out so I don't have any flashing lights to count. I hope someone can help me out racing season is about here.
If I had to quess, I would say you are not getting enough intake air at 4grand and above, You might have to put some kind of ram air on it. but again I am just guessing. at that rpm, flooding seems pretty much out of the question. double check air filter., If it is extreme,)to keep dust and fine stuff out, it may not be letting enough air in.
Usaully a bad o2 sensor would make the car run too rich, but it sounds like you don't have an ECU anymore? Have you converted to carb or do you have some kind of system to control spark and fuel delivery?
Usaully a bad o2 sensor would make the car run too rich, but it sounds like you don't have an ECU anymore? Have you converted to carb or do you have some kind of system to control spark and fuel delivery?
I thought about that, but I don't have any exhaust on the car.(it would only last a 1/2 lap) No, I've stayed with the TBI system. I ran an 84 Pulsar NX (carb) the last 3 years, but I think I cracked the head last lap of the A-main. What kind of chore would it be to convert the carb from this to the Sentra?
I've read that sometimes weak chassis ground could lead to rich mixture.
I've read that somewhere too. Isn't there a connection or something in the right rear of engine compartment that gets corroded? I'll have to dig around a little. Thanks for the help guys. If you think of anything else let me know.
if you are running TBI but have no comptuer thats your problem right there. A tbi is just a glorified computerized carb. it does a better job because its more precise but it can't be changed (well easily anyhow). So i'd suggest either put ecu in or swap to carb. although doesn't not having the ecu also mess up the timing?
__________________ Student at UTI Avondale 2nd place SkillsUSA/VICA WA State Automotive Maintenence '04 had an 87 pulsar...still planning CA20DET
1970 Chevy BelAir 350V8 300hp...soon to get M21
Running to rich 88 Sentra
Linear Mode
