98 V70 non-turbo near overheat problem

Post by **E Showell** » 19 Mar 2015, 06:32

After serial bad experiences with aftermarket ECTs -- I had more than one fail on me in a very short period of time -- like less than 10,000 miles, I determined that it just wasn't worth it to go aftermarket on the ECT. Volvo only for me from now on for that part. So yes, a failure of an aftermarket ECT after three years is very possible and would be consistent with my experience -- Note however, you may not want to base you actions on a study where n = 1.

ECT = Engine Coolant Temperature sensor.

Post by **98v70dad** » 19 Mar 2015, 07:21

E Showell wrote:After serial bad experiences with aftermarket ECTs -- I had more than one fail on me in a very short period of time -- like less than 10,000 miles, I determined that it just wasn't worth it to go aftermarket on the ECT. Volvo only for me from now on for that part. So yes, a failure of an aftermarket ECT after three years is very possible and would be consistent with my experience -- Note however, you may not want to base you actions on a study where n = 1.

ECT = Engine Coolant Temperature sensor.

n=6 is required to be statistically significant. I don't remember the brand name but I bought the ECT from a very reputable place that sells european car parts online and I believe it was the only choice (no volvo part). Maybe I'm remembering it wrong. I need to start writing this stuff down. It was one of the first of a litany of things that have failed and been replaced. Today I buy Volvo for most things, especially since the dealer near me has almost unbeatable online prices. I didn't know that at the time.

When the ECT failed last time I was getting a code that told me it had failed. Yesterday my gauge was showing an elevated temperature as it should have AND I wasn't getting any codes. Its also an extremely simple device that measures temperature through resistance change I think. That said they all fail eventually. The poor quality ones fail sooner and the good quality ones fail later.

Post by **E Showell** » 19 Mar 2015, 07:33

I never got a code in the most recent instance where my ECT failed.

Post by **rspi** » 19 Mar 2015, 08:36

98v70dad wrote:
E Showell wrote:I replaced that about three years ago with what seemed like a good quality an aftermarket part. I don't suspect that its failed this soon ...

No electrical part has a life expectancy. I replaced one with an OEM part that lasted a full 8 days. After market parts here are no better, most say they don't work at all.

Connect your OBD2 reader and read the live data temp and see what is going on. The fan should kick on at about 216 degrees and go off at 204. If that doesn't happen you need to figure out the issue. The water pump could be broken, not likely.

Post by **98v70dad** » 19 Mar 2015, 08:43

rspi wrote:
98v70dad wrote:
E Showell wrote:I replaced that about three years ago with what seemed like a good quality an aftermarket part. I don't suspect that its failed this soon ...
No electrical part has a life expectancy. I replaced one with an OEM part that lasted a full 8 days. After market parts here are no better, most say they don't work at all.

Connect your OBD2 reader and read the live data temp and see what is going on. The fan should kick on at about 216 degrees and go off at 204. If that doesn't happen you need to figure out the issue. The water pump could be broken, not likely.

I have a basic code reader. I don't think it will read live data. If it does I don't know how to do that, I'll have to check it out .... thanks.. Once I shut of the AC and got the coolant temperature back to normal, it stayed at normal for the remaining 10 mile drive home. I was shocked at how quickly it returned to normal once the AC load was removed. I doubt its the water pump, but it was on my list of things to suspect (near the bottom).

Post by **misha** » 19 Mar 2015, 09:11

In 1st post you said that cooling system parts(ect,thermostat) were replaced with OEM parts.Now you say that it's aftermarket part.

Only aftermarket ect sensor which can be used on these cars is Vernet besides oem Volvo which is actually made by Valeo.

If you,at first,said that you have aftermarket ect installed i would immediatelly said that it is your culprit.Aftermarket ect simply don't work with these cars,if it's not Vernet.

Now you have 2 possible culprits...aftermarket ect 99.9% or radiator fan relay.

Post by **98v70dad** » 19 Mar 2015, 11:25

misha wrote:In 1st post you said that cooling system parts(ect,thermostat) were replaced with OEM parts.Now you say that it's aftermarket part.

Only aftermarket ect sensor which can be used on these cars is Vernet besides oem Volvo which is actually made by Valeo.

If you,at first,said that you have aftermarket ect installed i would immediatelly said that it is your culprit.Aftermarket ect simply don't work with these cars,if it's not Vernet.

Now you have 2 possible culprits...aftermarket ect 99.9% or radiator fan relay.

Post by **98v70dad** » 19 Mar 2015, 11:26

misha wrote:In 1st post you said that cooling system parts(ect,thermostat) were replaced with OEM parts.Now you say that it's aftermarket part.

Only aftermarket ect sensor which can be used on these cars is Vernet besides oem Volvo which is actually made by Valeo.

If you,at first,said that you have aftermarket ect installed i would immediatelly said that it is your culprit.Aftermarket ect simply don't work with these cars,if it's not Vernet.

Now you have 2 possible culprits...aftermarket ect 99.9% or radiator fan relay.

I checked my records for the ECT purchase and the manufacturer of the part was SWF. The company I bought it from claimed it as an OEM part but I don't know. The part did not come in a volvo blue box although that doesn't really mean anything. Sorry I provided bad information. I am over 50 and don't always remember things as clearly as I did when I was younger. I know that Its important to know what you're dealing with when troubleshooting.

It has been almost exactly 5 years since I replaced it.

Post by **misha** » 19 Mar 2015, 14:53

SWF=Valeo=Oem Volvo
So we are good on Ect.Check it's contacts on both connectors,male & famale for corrosion.

Now that we determined that ect is correct,i would check relay.

Post by **98v70dad** » 19 Mar 2015, 17:24

misha wrote:SWF=Valeo=Oem Volvo
So we are good on Ect.Check it's contacts on both connectors,male & famale for corrosion.

Now that we determined that ect is correct,i would check relay.

Thanks. I stopped by the Volvo parts place and picked up the ECT and relay just in case I need them. I'll return whatever I don't need. Its been a long long day so I'm going to relax and have a glass of wine tonight. I'll get on the volvo problem tomorrow night or Saturday morning. Its not normal for me but this week I have two cars at home while my wife is away so the volvo can wait.

I also picked up a can of electrical connector cleaner. I already have some dielectric grease.

Thanks to everyone's help and comments I'm now prepared to have a good chance of fixing the problem on the first try.