97 crown vic ect position

97 vic 4.6L w code engine. does this have 2 ect on it? intake has 2 sensors in front on same water passage. 1 on drivers side and 1 on pass side next to gauge sending unit. which one is the ect? getting a lot of spark knock with no codes stored/visible. dealer suggested checking ect,act,egr systems. haven't yet checked egr ports and act values within specs I have.
Reply to
dmac
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dmac opined in news:411e5bb5 snipped-for-privacy@newspeer2.tds.net:

the dealer SHOULD have checked/cleaned the MAF*, dunno about the ECT's... I do know the engine wont start without flooring pedal when it's disconnected.

Should be a two-wire connecter.

*Disconnect MAF, see if it runs better.

see tccoa.com for cleaning directions

Reply to
Backyard Mechanic

Sounds like the EGR passage is dirty, I've heard of that happening on a lot of 4.6L's. See this for more info.

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Reply to
Swanny

I will get MAF checked after verifying the ect question. I suspect its not MAF since car only knocks after fully warmed up. knock sensor was in range, and what a pain that is to get at.. see my post to Swanny about ect ohm test.

Reply to
dmac

Thanks for the link. I was going to check out the ports in the next few days just to rule them out, this link will help! The dealer and I discussed the ports extensively and we think its not the reason for the spark knock, but as a last resort we figured to try it. I,and dealer agreed, think it's a bad ECT that's causing a too lean condition. It really looks like 2 ect sensors there on the one water passage, separated by about 3 inches. This morning before running the vehicle I ohmed the sensors.at an ambient temp of about 80 deg F 1 read 25 ohms, which is what it should be for that temp. the other ohmed out to 5 ohms which correlates to about 175 deg F. after running vehicle the first one ohmed to 5, which is within tolerances. The second read 1 ohm, which correlates to 240 deg F. I think that's causing a lean out at operating temp which is causing the spark knock. I'll find out as soon as I verify they are both ect sensors.

dmac

Reply to
dmac

The following information is for my '92 but it should probably hold true for your '97: The sensor near the #1 fuel injector on the passenger side is a coolant temperature sensor that feeds the instrument cluster only. The sensor closer to the thermostat housing on the driver side is the Engine Coolant Temperature (ECT) sensor that feeds the computer. The resistance of it should be 24,270 ohms at 86 degrees F and 2800 ohms at 194 degrees F. My money is on the MAF. Clean it quickly... takes only a few minutes of time. Stan K.

Reply to
Stan Kasperski

I'll give that a shot tomorrow. whats best way to clean it? the sensor near thermostat ohmed ok but the other was way off from the ect specs I had. but if that other is just the gauge sender its probably correct.

egr ports were checked today and were ok. not squeaky clean but no blockage either. fuel pressure and flow were ok too. I have to check the act and clean maf now I guess. its odd because it only knocks when engine is hot and ambient air temp affects it too.

5 brands of gas (all three grades) didn't help either.
Reply to
dmac

yes, that is the way it happens. pings when hot. clean the MAF and put a fuel filter on it if its been a while.

Reply to
Scott M

ok, cleaning mAF and ect/act contacts has helped a lot. no knock for last 2 days under full throttle now. am putting new fuel filter on both my vehicles saturday anyways so that works out well too.

Thanks everyone.

Dmac

Reply to
dmac

ok, cleaning mAF and ect/act contacts has helped a lot. no knock for last 2 days under full throttle now. am putting new fuel filter on both my vehicles saturday anyways so that works out well too.

Thanks everyone.

Dmac

Reply to
dmac

dmac opined in news: snipped-for-privacy@posting.google.com:

Well... I've found that is the condition a dirty MAF presents; and now, so have you. ;)

Reply to
Backyard Mechanic

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