Need help about throttle body
Need help about throttle body So, we just rebuilt our lt1, bored it .030 over, put a hotcam in it.
For christmas I got a 58mm Throttle Body and a new thermostat (Had holes in the old one due to...ugh...bad experiences with heat?)
So today I went and put it on, FYI its BBK brand, it does have 2 hoses deleted coming from the radiator.
Put thermostat in, attached TB, and started it, the car is idleing at 600 and cutting out when given gas. So I cut it off, and tried her again, gave it a little more gas then it got hung on 1500 rpms for idle. I looked under the hood it is spewing water from the metal T. Any idea on what this is? Before I put the cap over the throttle cables, I was playing with it, it seems to get stuck when you open it full throttle and let it slam back, I think thats just paint causing it to stick. Can their be paint on the spring causing it to be sticky?
I kinda need my car tonight so any help to make it run would be great. It's also missing the knock sensor but I have one arriving in an hour or two.
For christmas I got a 58mm Throttle Body and a new thermostat (Had holes in the old one due to...ugh...bad experiences with heat?)
So today I went and put it on, FYI its BBK brand, it does have 2 hoses deleted coming from the radiator.
Put thermostat in, attached TB, and started it, the car is idleing at 600 and cutting out when given gas. So I cut it off, and tried her again, gave it a little more gas then it got hung on 1500 rpms for idle. I looked under the hood it is spewing water from the metal T. Any idea on what this is? Before I put the cap over the throttle cables, I was playing with it, it seems to get stuck when you open it full throttle and let it slam back, I think thats just paint causing it to stick. Can their be paint on the spring causing it to be sticky?
I kinda need my car tonight so any help to make it run would be great. It's also missing the knock sensor but I have one arriving in an hour or two.
Make sure that TB has a hole for idle air. If not, that will most likely be the problem of your idle issues. I think the stock size should be 11/32". Either search or google LT1 TB drill mod.
Its a bbk tb, and VERY old, I'm thinking about adjusting the blades first and then calibrating the tps sensor before I rule any sensors out as bad, if they're bad I'll switch his stock tb sensors for the bbk sensors.
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If it's as directly from BBK, it won't have the bleed hole. You'll definitely need to set the blades and adjust the TPS in order to get the IAC back where it needs to be. As for the sticking issue, my BBK 58mm took essentially a tear down and clean up of a bunch of gunk around the blades for it to operate smoothly. I was VERY surprised at the poor quality directly from BBK. Afterwards, the only problem I've had since was the linkage to shaft connection coming loose, but a tack weld fixed that.
I don't believe the stock bleed hole is 11/32 as that's over 1/4" in size, and LARGE. I think 11/64 was a closer size to stock. START SMALL AND COME UP, but only AFTER getting the blades/TPS set. You might not even need the bleed hole at all.
I don't believe the stock bleed hole is 11/32 as that's over 1/4" in size, and LARGE. I think 11/64 was a closer size to stock. START SMALL AND COME UP, but only AFTER getting the blades/TPS set. You might not even need the bleed hole at all.
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If you are running a 58mm, assume you had intake machined out larger for it, you also need to have PCM adjusted for A4 or tranny damage can happen
Aftermarket TB's are not "plug & play" and typically have idle issues like you have. You need a scan tool to measure your IAC counts. 32 (30-35) is where you want them with car at operating temp at idle and if high drill 1/8" hole between blades like on your stock TB. Measure IAC counts again and if still to high drill 1/64" larger . TAKE BABY STEPS 1/64" MAKES A BIG DIFFRENCE.
I would not blindly drill a hole without first monitering the IAC counts to see WTF IAC counts are.
If you are running a 58mm, assume you had intake machined out larger for it, you also need to have PCM adjusted for A4 or tranny damage can happen
Aftermarket TB's are not "plug & play" and typically have idle issues like you have. You need a scan tool to measure your IAC counts. 32 (30-35) is where you want them with car at operating temp at idle and if high drill 1/8" hole between blades like on your stock TB. Measure IAC counts again and if still to high drill 1/64" larger . TAKE BABY STEPS 1/64" MAKES A BIG DIFFRENCE.
I would not blindly drill a hole without first monitering the IAC counts to see WTF IAC counts are.
Sounds right. Either way, if it's a stock sized displacement it shouldn't need anything over what stock is. The diameter on my TB for my 396 is stock sized and it idles perfectly.
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cracking TB blades open has worked. just measure your TPS volts to see if they are still within range. if off to much, shift points can be effected but fortunately there is +/- room on either side of .67vdc ish blades closed to not be a issue.
some "slot" the holes in TPS to allow it to rotate slightly to a position it is happy with with the new TB blade position. you just need to measure IAC volts with a meter to see what they are closed and full open. .67vdc closed and 4.5 vdc full open is "ideal" but again there is some "room" if one side or the other of those readings
some "slot" the holes in TPS to allow it to rotate slightly to a position it is happy with with the new TB blade position. you just need to measure IAC volts with a meter to see what they are closed and full open. .67vdc closed and 4.5 vdc full open is "ideal" but again there is some "room" if one side or the other of those readings
like ed and moe said, always avoid drilling holes at all costs, open the blades a bit till your iac counts at idle are around 10-20 then clock the tps back so the ecm reads 0% throttle, ive got an old bbk 52mm on my truck with no holes and a stock 95 cam, did it this way and it runs mint never a starting or idle issue even on a 5* morning like today
