It's about my '95 pickup. Every early morning, when I start up thr engine. The idle with higher RPM & pitch will last about 7 min.; then drop back to normal idling with lower sound. Is this normal????
- posted
19 years ago
It's about my '95 pickup. Every early morning, when I start up thr engine. The idle with higher RPM & pitch will last about 7 min.; then drop back to normal idling with lower sound. Is this normal????
snipped-for-privacy@hotmail.com (Matt) spake unto the masses in news: snipped-for-privacy@posting.google.com:
Absolutely.
Read The Owner's Manual.
It's called "cold fast idle".
And you should not be letting it idle for 7 minutes. 30 seconds is plenty.
I never let any of my car idle. Well, Maybe I should simply say the rpm will not drop from the cold engine until 7 minutes later. Usually, I start up the car and go. The rpm is high with cold engine; any stop within the first 7 min; the rpm is high. My question is the first 7 min seems too long for a car to drop the rpm back to normal.
snipped-for-privacy@hotmail.com (Matt) wrote in news: snipped-for-privacy@posting.google.com:
Yes
MLB wrote in news:Xns94F68C9F3CC65mikeb46815yahoocom@216.196.97.136:
That's "yes" to 7 minutes is too long. Somethings not kicking in like it should. Mine drops in less than a minute.
Matt,
You could possibly have a bad radiator thermostat. This is not allowing the coolant to by-pass the radiator until operating temperatures. Which brings up the question, does the high rpm correlate with your engine temperature??
Tony
Most of the noise you may be hearing is the "coupled" clutch fan which really pulls lots of air and sounds like a higher rpm that it really is. But it uusally last no more than a minute
Hi Tony, The high rpm does not correlate with my engine temperature. Temp stays
1/9 of the temp range, unless lots of traffic stops with long idling or in a very hot day, then temp goes up to normal high (less than half of the temp. range). Never overheat. Quiet and smooth, running like a champ with 30 mpg(4banger w/stick shift 5 speed). I feel O2 kicks in after that 7 min. ECM seems delay in sending late signal. Sensonrs problem. No idle fluctuation, rough idle, stumbling, vaccum leak etc. Usually, temp gauge will show overheating if the thermostat is sticky or malfunctions. Isn't it?Matt
Hi MDT Tech®, You are right about "Most of the noise you may be hearing is the "coupled" clutch fan which really pulls lots of air and sounds like a higher rpm that it really is." The fan running makes noise for that long, 7 min., along with high rpm. What goes wrong???
The high rpm does not correlate with my engine temperature. Temp stays
1/9 of the temp range, unless lots of traffic stops with long idling or in a very hot day, then temp goes up to normal high (less than half of the temp. range). Never overheat. Quiet and smooth, running like a champ with 30 mpg(4banger w/stick shift 5 speed). I feel O2 kicks in after that 7 min. ECM seems delay in sending late signal. Sensonrs problem. No idle fluctuation, rough idle, stumbling, vaccum leak etc. Usually, temp gauge will show overheating if the thermostat is sticky or malfunctions. Isn't it?Matt
snipped-for-privacy@hotmail.com (Matt) spake unto the masses in news: snipped-for-privacy@posting.google.com:
Sure sounds like a bad thermostat to me.
They go bad two ways:
1) Stick shut and cause overheating 2) Stick open, causing cold running.How's your heater output? Bet it's poor.
Our old MR2 suffered from exactly this. Since it had an automatic, it had the additional symptom of refusing to shift into overdive until you had driven a long, long way.
Thermostats are cheap and easy to change. Try it.
Tegger,
That is what I am thinking also.... You have a bad thermostat not allowing your engine to warm up.. NORMAL operating range is in the middle..
Tony
The culprit is thermostat. I replaced with a new one and gasket. temp is normal, and idle is so quiet and smooth now. Van't believe thermostat only lasts 51K (mine is low milledge). Thanks for everyone's help. Matt
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