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I would also replace you intake manifold bolts with ARP 130-2001 replacement bolts, when I did my oil pressure sensor 2 months ago I felt like my stock manifold bolts were going to break so I could only torque them to 65 in-lbs instead of the 89 in-lbs spec.
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St. Jude Donor '25
Originally Posted by Monty23
I would also replace you intake manifold bolts with ARP 130-2001 replacement bolts, when I did my oil pressure sensor 2 months ago I felt like my stock manifold bolts were going to break so I could only torque them to 65 in-lbs instead of the 89 in-lbs spec.
Well those are pricey, but they will be here tomorrow. The last thing I need is to break one of those. Thanks for the advice!
I would also replace you intake manifold bolts with ARP 130-2001 replacement bolts, when I did my oil pressure sensor 2 months ago I felt like my stock manifold bolts were going to break so I could only torque them to 65 in-lbs instead of the 89 in-lbs spec.
I would also replace you intake manifold bolts with ARP 130-2001 replacement bolts, when I did my oil pressure sensor 2 months ago I felt like my stock manifold bolts were going to break so I could only torque them to 65 in-lbs instead of the 89 in-lbs spec.
Those stock bolts are one Helluva lot stronger than the aluminum block/heads they screw into, and stronger than the factory intake, too. ARP fasteners are great......Where they're needed. The intake bolts aren't one of them...
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St. Jude Donor '25
Many thanks to everyone for the advice. I pulled the intake yesterday and relocated/replaced the oil pressure sending unit under the fuel rail cover. It went pretty smoothly overall, and it took about 7 hours, but I was very careful - especially about cleaning everything - and I took lots of pics along the way.
I added 5" of vacuum line to the rear of the intake. That vacuum line is 1/4" on my 2000.
with a 45 degree fitting that attached to the fitting in the block and routes the hose at a nice angle to hide the sender under the fuel rail cover. And
.
I did use the new ARP manifold bolts. I'm sure the old bolts were plenty strong enough, but when I removed them the factory thread lock on them made them feel tight in the threads. I didn't think those bolts - without a lot of cleaning - would have the proper torque on the re-install.
The car started right up with no leaks and is running great. I'm glad I don't have to pull that intake very often.
Last edited by Six7390gt; Sep 16, 2025 at 02:02 PM.
Those stock bolts are one Helluva lot stronger than the aluminum block/heads they screw into, and stronger than the factory intake, too. ARP fasteners are great......Where they're needed. The intake bolts aren't one of them...
I get what you are saying, but my bolts were yielding so I needed replacements. Clearly the stockers were not up to the task from my experience and seeing other people on here breaking bolts. Are you saying you would just put new stock bolts back in? An hour of my time screwing around with a broken bolt is worth much more than $38 for ARP fasteners, at least to me. And Amazon had them available next day. YMMV.
Then your torque is way off. The service manual specifically calls for threadlocker, and the required torque spec takes that into account. That's why it probably felt like the bolts would snap without threadlocker.
Then your torque is way off. The service manual specifically calls for threadlocker, and the required torque spec takes that into account. That's why it probably felt like the bolts would snap without threadlocker.
Torque would not be way off. Total clamp force would be off if the friction coefficient is not correct due to the lack of the thread lock (which would act as a lubricant) at the same torque value. This is a confusing subject, so please don't take my comments as insulting. For example, if you tighten a new bolt that is cross threaded before the head of the bolt makes contact with the intake manifold, you should have no problem reaching 89 in-lbs of torque, but the clamp force squeezing the intake manifold to the head would be 0 lbf when it should be about ~6k lbf each for an M6 thread. In a different example, if I applied a lubricant that had a much lower coefficient of friction (more slippery), then as I tightened the bolt to 89 in-lbs my clamp force would be much higher and this would potentially yield/stretch/break the bolt like you suggest.
My issue was that when trying to torque to 89 in lbs, the head started rotating way too much which is a great indicator that the bolt is stretching vs. increasing in clamp force.
I get what you are saying, but my bolts were yielding so I needed replacements. Clearly the stockers were not up to the task from my experience and seeing other people on here breaking bolts. Are you saying you would just put new stock bolts back in? An hour of my time screwing around with a broken bolt is worth much more than $38 for ARP fasteners, at least to me. And Amazon had them available next day. YMMV.
No I didn't.
I have NEVER broken an intake bolt, and NEVER had any come loose. I've had the same intake bolts for over 20 years, on 3 different engines, and 3 different intakes. Maybe your engine got a bunch of junk bolts straight from GM. I've never torqued them either, however, I do have a lot of wrenching experience. I still think the OEM bolts are more than adequate for an aluminum engine and plastic intake. But maybe some OEM bolts are not adequate. Have to be some pretty bad steel to have plastic and aluminum have greater strength than steel!!!
Torque would not be way off. Total clamp force would be off if the friction coefficient is not correct due to the lack of the thread lock (which would act as a lubricant) at the same torque value. This is a confusing subject, so please don't take my comments as insulting. For example, if you tighten a new bolt that is cross threaded before the head of the bolt makes contact with the intake manifold, you should have no problem reaching 89 in-lbs of torque, but the clamp force squeezing the intake manifold to the head would be 0 lbf when it should be about ~6k lbf each for an M6 thread. In a different example, if I applied a lubricant that had a much lower coefficient of friction (more slippery), then as I tightened the bolt to 89 in-lbs my clamp force would be much higher and this would potentially yield/stretch/break the bolt like you suggest.
My issue was that when trying to torque to 89 in lbs, the head started rotating way too much which is a great indicator that the bolt is stretching vs. increasing in clamp force.
Not confusing for me ......and yes, I was trying to keep it simple...I should have elaborated more to distinguish clamp force achieved v/s torque. Not everyone has your background, which even makes the outcome more surprising.
You do you.
Dorman sensor failed in 3 weeks, shopping at O'Reilly
Originally Posted by eyekyu
you do not need to drain the coolant. Make an oil pressure sensor relocation kit and make you you also extend the harness.
heres a link for Harness extension. https://www.amazon.com/dp/B07TLZC8FK
as for the oil pressure sensor, Ive had great luck with Dorman sensor, been running it for 2 years now. Orileys has a lifetime warranty for them. Dorman 926-040
->Great thread.. I've used Dorman parts successfully for years on various cars, including a previous and my current '03 C5 for window motor assemblies. So I bought the 926-040 sensor from Amazon (Under $30 vs O'Reilly price as below, double that amount!) and it has failed in about 3 weeks. Below is what I find on O'Reilly, which of the other two is recommended? Either can be found much cheaper, I'm leaning towards the pricey one from Standard which Summit Racing has for $43.00 versus $73.00.
I was interested to see that the failure is inside the switch, the burning oil smell came from it leaking up through the top on to the engine. I guess it just couldn't handle the pressure and the oil just leaked through the unit. So lame. BUT via Amazon/Dorman I fairly easily am getting a cash refund (like I care about $30 versus the afternoon I'm going to have to devote to doing this job a second time). Failed Dorman sensor full of oil.
Yeah, you are getting a refund for the product but what is your time/materials worth? What if you hired someone to do the work and had to pay a mechanic twice ...plus now you have to degrease the engine.
I avoid Dorman products if humanly possible, and I do not buy parts of Amazon. It's a dice roll.
The Standard Motor Products PS308 is a no brainer.
I honestly don't know who made my sender. I got the 1 year guaranteed one at O'Reilly, but that was least 8 years ago, and it's still good. But they may sell a different brand (read: cheaper) now. So it's tough to recommend even good brand names anymore, due to global ownership. Fram was once a top brand filter. Even Wix is now owned by a Chinese company. Whether they're as good as before, who knows? What was once a good sender (or anything else) may no longer be. I do think some people tighten the bejesus out of things. OP: When you get the new sender, put some teflon tape or pipe sealant on it, and either torque it to spec, or use an "experienced feel." As Lucky said, stay away from Amazon for critical, and hard to access parts. Bezos (Bozo?) will think nothing of taking your hard earned money as he's drilling his 30 year younger wife!!
Yeah, you are getting a refund for the product but what is your time/materials worth? What if you hired someone to do the work and had to pay a mechanic twice ...plus now you have to degrease the engine.
I avoid Dorman products if humanly possible, and I do not buy parts of Amazon. It's a dice roll.
The Standard Motor Products PS308 is a no brainer.
If you paid someone else to do this, you would not be paying again if the part failed. That's the risk the mechanic takes.
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St. Jude Donor '25
[QUOTE=DWC4;1609363393]->Great thread.. I've used Dorman parts successfully for years on various cars, including a previous and my current '03 C5 for window motor assemblies. So I bought the 926-040 sensor from Amazon (Under $30 vs O'Reilly price as below, double that amount!) and it has failed in about 3 weeks. Below is what I find on O'Reilly, which of the other two is recommended? Either can be found much cheaper, I'm leaning towards the pricey one from Standard which Summit Racing has for $43.00 versus $73.00.
I was interested to see that the failure is inside the switch, the burning oil smell came from it leaking up through the top on to the engine. I guess it just couldn't handle the pressure and the oil just leaked through the unit. So lame. BUT via Amazon/Dorman I fairly easily am getting a cash refund (like I care about $30 versus the afternoon I'm going to have to devote to doing this job a second time). Failed Dorman sensor full of oil.
Well that sucks - sorry to hear that happened. The sensor was pretty easy to relocate up under the driver's side fuel rail cover. I listed links to the parts I used to relocate it in post #25.
I hope you have better luck with your next sensor. I did end up using the Genuine GM Parts 12677836 sensor from Amazon, and it's been fine.
->Great thread.. I've used Dorman parts successfully for years on various cars, including a previous and my current '03 C5 for window motor assemblies. So I bought the 926-040 sensor from Amazon (Under $30 vs O'Reilly price as below, double that amount!) and it has failed in about 3 weeks. Below is what I find on O'Reilly, which of the other two is recommended? Either can be found much cheaper, I'm leaning towards the pricey one from Standard which Summit Racing has for $43.00 versus $73.00.
I was interested to see that the failure is inside the switch, the burning oil smell came from it leaking up through the top on to the engine. I guess it just couldn't handle the pressure and the oil just leaked through the unit. So lame. BUT via Amazon/Dorman I fairly easily am getting a cash refund (like I care about $30 versus the afternoon I'm going to have to devote to doing this job a second time). Failed Dorman sensor full of oil.
Well that sucks - sorry to hear that happened. The sensor was pretty easy to relocate up under the driver's side fuel rail cover. I listed links to the parts I used to relocate it in post #25.
I hope you have better luck with your next sensor. I did end up using the Genuine GM Parts 12677836 sensor from Amazon, and it's been fine.
I’m giving it a shot, thanks. But why doesn’t someone make a bulletproof proof one? I’d gladly pay $100 for a 100% reliable (ok, 99%) part.
The Dorman came with this filter, which I saw no way to attach. What’s the deal?Does it go in before the sensor, maybe protect it in some way?? came with Dorman sensor this one comes with filter too.
Last edited by DWC4; Jan 10, 2026 at 04:46 PM.
Reason: update
Many times, I go with OEM parts, ESPECIALLY things like lifter trays and O2 sensors. However, the OEM oil pressure senders are as reliable as an ex-wife's testimony at a custody hearing. Yeah, I like that metaphor. No, I dont run the OEM senders. They can fail in either direction. When they read 130lbs, you know something is up. When they fail and read ZERO, your underwear can get in a twist MIGHTY quick! Don't ask........
