oil pressure new isspro sender fitted
Discussion
That's reading nonsense then!
I've just been out for a cruise on the old sender,
Cold starts and I get 30psi reducing to about 10 psi when hot
Running anything over about 2000 revs mine sits at 25 psi and goes upto 30 psi when over 3000 revs.
I've used a mech gauge and it's accurate upto 30 psi where my sender stops but the mech gauge goes upto 45/50 psi
It shouldn't move until the engine fires and pressure builds?
I've just been out for a cruise on the old sender,
Cold starts and I get 30psi reducing to about 10 psi when hot
Running anything over about 2000 revs mine sits at 25 psi and goes upto 30 psi when over 3000 revs.
I've used a mech gauge and it's accurate upto 30 psi where my sender stops but the mech gauge goes upto 45/50 psi
It shouldn't move until the engine fires and pressure builds?
dc400 said:
Thanks for the reply as I said the old one ran at about 25-30 but folks keep saying the originals are not accurate ,so I didn't know about the new one. I will ring the dealer tomorrow.Thanks again.
No worries 
No they are not entirely accurate, by using a mechanical gauge I ascertained the original sender is pretty accurate on tickover and upto about 3000 revs when oil is warm.
And yes with a mechanical gauge my oil pressure was as low as 10 psi at tickover which is what the Tvr sender reads.
So for all but high revs my Tvr gauge reads accurately.
For some reason my Tvr gauge sticks at around 30 psi over 3000 revs, where as the mech gauge the pressure over 3000 revs is around 40 psi and rising to 50 cold/ 45/50 psi hot.
I did this test on a very warm summers day and even sat the car at 90 degrees on tickover for an extended period to get the oil very hot before driving with gauge sticking out the top of the bonnet
You've attached the extra ground wire,
Have you connected the two wires correctly.
My description pic suggests they have to be correctly wired.
dc400 said:
Yes ground wire connected ,as pics ,I even swapped the wires over just in case but still got the same readings.
Hmmm, that's not great! Stupid question but it is the 0/100 psi because there's one with the same part number that's 0/80 psi.
Must be faulty then.
I've still not found the time to do mine, maybe I should make an effort as this doesn't sound good!
ClassiChimi said:
dc400 said:
Yes ground wire connected ,as pics ,I even swapped the wires over just in case but still got the same readings.
Hmmm, that's not great! Must be faulty then, I've still not found the time to do mine, maybe I should make an effort as this doesn't sound good! 1. Unscrewed my old cheapy Chinese eBay sender that was still working after 5 years (only replaced it because it was weeping a little oil)
2. Jacked the engine slightly to get the new longer body Isspro sender started on the thread
3. Tightened it, lowered the engine checking it didn't foul anything and connected it up (I'd already made the earth lead when I fitted the old eBay sender 5 years ago)
4. Started the engine to check for leaks (there were none), and correct operation/readings (worked perfectly)
5. Lowered the car and have not given it a second thought
My OP gauge reads pretty much exactly the same figures as the old cheapy Chinese sender gave so other than the longevity test I called the Isspro unit a leak free accurate reading success. I have no idea if the more expensive Isspro sender will last longer than the 5 years I enjoyed from the the old cheapy Chinese one, but I can 100% guarantee you it was a straight swap and it works absolutely perfectly.
I hope dc400 gets it sorted, my guess is you have a bad earth or a short in your gauge wire, the gauge is quite a delicate instrument, the range of resistance it and the sender operate in means it's easily affected by unwanted influencing currents or sources of resistance, even very small ones. This all means the the wiring needs to be absolutely spot on for everything to work as it should and sadly makes oddball readings quite common.
Good luck with it, but please make no mistake this Isspro sender is a straight swap that in my experience works perfectly.
Hi,just in from work, I fit the new unit the same as Chimpongas as I had read an earlier topic about fitting so I knew about lifting engine a little to give room for longer sensor and it was easy to fit .I used the original wire to gauge .The earth wire I put on is a bit heavier than the gauge wire would this affect the readings
dc400 said:
Hi. I have just replaced my oil pressure sender with a Isspro sender I need to know what normal oil pressure is. Before the old one packed in it read between 25-35 the new one is showing 15 with just ignition on -50 at tick over and 55-60 at 2500-3000revs .Any advice welcome Thanks.
I've just fitted my Isspro oil sender and I have the same results! Here's a pic anyway.
Unfortunately my V8F (long) oil filter won't fit without some spacers to lift the engine by 5mm because it sits to close to the cross brace but luckily I'd also purchased a UFI filter off Richard 858 so I was able to carry on and replace the oil and filter anyway.
Adding spacers or washers to lift my engine position, will this add stress to the drivetrain or will the gearbox swivel upwards in line with the engine?
Thanks Al
Hi ClassicChimeara. I have not had time to look at mine due to work but I am going to try new cables this weekend .I got the Isspro sender as I hade read on the forum that they were more accurate I can take my sender to work to get it checked as I contacted the supplier and he said if its ok it should show 240 ohms resistance .a sparky will check this for me. I will let you know results after I change wires
dc400 said:
Hi ClassicChimeara. I have not had time to look at mine due to work but I am going to try new cables this weekend .I got the Isspro sender as I hade read on the forum that they were more accurate I can take my sender to work to get it checked as I contacted the supplier and he said if its ok it should show 240 ohms resistance .a sparky will check this for me. I will let you know results after I change wires
Yes testing the sender will at least tell us if it's doing the job. I notice there's a fibre plate below both the bolts, this to me tells me it can be wired either way, can anyone confirm this?
Cheers Al
ClassicChimaera said:
bobfather said:
^^are you saying these senders read 15psi before the engine starts?^^
If so, I'd go find a better sender, that reading is total b0ll0cks
Unfortunately yes. If so, I'd go find a better sender, that reading is total b0ll0cks
I'll let it cool down then take a few pics of the gauge at different temps and revs.
It looks that way.
Mines a 2000 year car so on the cusp of being a Mk3
I'm just so thankful another Tvr friend lent me his mech gauge or I'd be totally confused.
Considering the mech gauge was on the end of a 1m length of hose it still read accurately, if anything a bit low but you could clearly see the pressure build and fall in line with revs
To be clear
Engine hot using mechanical gauge
1000 revs 12/15 psi,,
2000 revs 25
3000 revs and above 45/50 psi.
So when your Tvr gauge reads low on tickover it's totally normal.
When I deliberately got the engine as hot as I could, drove it hard then let it stand with fans kicking in and out at least twice I got a reading as low as 10 psi on the mech gauge (the same as my Tvr gauge) at a low 650 revs tickover.
Mines a 2000 year car so on the cusp of being a Mk3
I'm just so thankful another Tvr friend lent me his mech gauge or I'd be totally confused.
Considering the mech gauge was on the end of a 1m length of hose it still read accurately, if anything a bit low but you could clearly see the pressure build and fall in line with revs
To be clear
Engine hot using mechanical gauge
1000 revs 12/15 psi,,
2000 revs 25
3000 revs and above 45/50 psi.
So when your Tvr gauge reads low on tickover it's totally normal.
When I deliberately got the engine as hot as I could, drove it hard then let it stand with fans kicking in and out at least twice I got a reading as low as 10 psi on the mech gauge (the same as my Tvr gauge) at a low 650 revs tickover.
Essentially yes, I'm now re calibrating my brain to read the gauge with these new levels but it's not good.
It's not as accurate as my original at the lower revs when hot so unless we can get one that does work I'll go back to the original.
Good if you want to sell, not very good if you want to know your true pressure.
Sadly Dave it hasn't worked for a couple of us, no worries as I've learnt that these experiments are just that, if it had worked I'd be stoked.
Mechanical gauge is how I'd like to go with a TVR face on the front
Anyone got any ideas
It's not as accurate as my original at the lower revs when hot so unless we can get one that does work I'll go back to the original.
Good if you want to sell, not very good if you want to know your true pressure.
Sadly Dave it hasn't worked for a couple of us, no worries as I've learnt that these experiments are just that, if it had worked I'd be stoked.
Mechanical gauge is how I'd like to go with a TVR face on the front
Anyone got any ideas
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