Help with Coolant Pressure Readings

[Fox Hunt]

Day 1- Stock tuning, once I got it up to temps pressure was 5psi consistently on the highway. WOT runs up to 70mph it would hit 7psi or so. Going up a steep hill ECT got up to 208* and reached 10psi.

Day 2- SRL tune for my pmax. Once up to temps I did some WOT to 70 again would hit 16psi and come down to 15psi. Then once on the highway pressure was a consistent 14psi. Then running up the same hill the day before ECT got up to 208* again and pressure was 15psi.

I have a washer in the up pipe with a 1/4in hole to prevent CEL when not tuned (plan on just plugging it all together when I have time). Also when the truck hit 16psi tuned, I looked under the hood and didnt see any coolant spewed all over, but I guess the coolant wouldnt have to come out as long as gas pressure is released.

Not sure how to decipher this. Does tuning really add that much more pressure to the system? Just thinking out loud, but by not allowing the gas to really escape the egr cooler when tuned, could I have a small in the cooler and with the gases not going anywhere, build pressure in the system? Because stock the egr valve would be open allowing gas to flow through? Maybe someone else has some other ideas or theories.

[colonel angus]

I've been wondering and measuring almost the same results, only difference is mine will hit 15 PSI stock or tuned, just quicker with a tune and I have an EGR delete from bulletproof and am running Eric's Street Perform Tune.

Because of this pressure in coolant I've decided I have a HG leak and put the truck in the shop for ARP studs and oem gaskets.

Denny

[Fox Hunt]

Well if you are experiencing the same situation a me I'll be interested to hear your new readings after you get your head studs done.

[PGreenSVT]

with the SRL+ and the Pmax/Batmo combination I would expect your egt's to be higher leading to higher ECT's. If high enough to boil the coolant you are going to see a pressure rize. You have a tuner which can kill the light so why not close the egr cooler off all the way?

Oddly enough with the same setup and 175/75 sticks behind it climbing a decent grade (say 4% or so) at 75 mph I will easily see 1350*+. I can either back out of it and downshift to 5th gear or I can speed up to 90 mph or a tad more. Either one will lower my EGT's.

I have no EGR cooler (Sinister delete) and have a BPD remote oil cooler so my coolant temps and oil temps are a different matter. I don't run stock so I couldn't tell you what happens then.

[colonel angus]

I should mention i changed from Gold to ELC and didn't see any difference, but not the sole reason for changing over. Also have the Sin. Coolant Filter.

D

[Fox Hunt]

Originally Posted by PGreenSVT

with the SRL+ and the Pmax/Batmo combination I would expect your egt's to be higher leading to higher ECT's. If high enough to boil the coolant you are going to see a pressure rize. You have a tuner which can kill the light so why not close the egr cooler off all the way?

Oddly enough with the same setup and 175/75 sticks behind it climbing a decent grade (say 4% or so) at 75 mph I will easily see 1350*+. I can either back out of it and downshift to 5th gear or I can speed up to 90 mph or a tad more. Either one will lower my EGT's.

I have no EGR cooler (Sinister delete) and have a BPD remote oil cooler so my coolant temps and oil temps are a different matter. I don't run stock so I couldn't tell you what happens then.

I life in Ca so I was trying to be safe. Now that I know you can run even a tow tune to pass tests I will plug it and not worry.

[Fox Hunt]

If my ect temps are the same whether I'm tuned or not, I would think my pressure would be the same. Unless its possible to have a leak in a head gasket or egr and it not leak until a high tune is on? am I way off here?

[colonel angus]

If I'm not mistaken the ECT's will always be close because the thermostat will regulate them.

I have perfect temps around 192 ish regardless and pressures in excess of 15 psi and mild puking and head gaskets going in with ARP studs.

Denny

[Six0~Stroker]

Yes the thermostat controls the coolant heat!

Mine stays at 190-193 with a stock tune or Erics Extreme Street..


But if I romp on it the temp will rise

[2003kingranch]

I was monitoring my coolant pressures for a while. Driving normal (under 10lbs off boost)stock or tuned all day my coolant pressure wouldn't go over 5-7 psi. But if I get on it a few times (not wot) it will climb to 15-16 and sit there. Caps venting of course. And puking at wot tuned. My ect sits at 188-190 tuned, stock, or towing (at 5k and under)


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