Question about 1994 Chevrolet Corvette

2 Answers

Engine running hot at idle and low speeds. secondary fan not running.

Posted by on

Ad

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Chevrolet Master
  • 2,359 Answers

The secondary fan is working conjunction with the A/C system.

When the computer (ECU) sense the load

Example: going 40% grade/hill and A/C is on the fan will kicks in.

Test 2nd fan relay by apply 12V power to test the fan.

Test fan relay.

Posted on Dec 05, 2009

Ad
  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    MVP:

    An expert that got 5 achievements.

    Governor:

    An expert whose answer got voted for 20 times.

    Scholar:

    An expert who has written 20 answers of more than 400 characters.

  • Expert
  • 176 Answers

Fix the secondary fan.

Posted on Sep 11, 2009

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
New users get 2 Free calls (no credit card required) and instant help on almost anything you can think of (from cars to computers, appliances, handyman, and even pets).
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

How to adjust idle?


hot engine ?, cold or both,, EFI runs in 3 modes, cold ,warm and hot.

name it.

which engine option (displacement)??????



there is no idle adjust, that is the PCMs, job 100%, all the time.

Carbs are gone.

here is rule one for all EFI.

idle is the last thing to work correctly.

anything the causes a gross imbalance of engine power to engine load, under idle will cause , idle controls to fail.



low idling causes. (over 50 but, here ar basics)

1: AFR (air fuel mixture too lean) usually surges. (clogged or leaking injectors. or fuel pressure way to high)

2: air leaks, cause racing, so not that. (speed density car ,if is)

3: egr stuck open. low idle and misfire.

4: ISC stuck closed (IAC electric)

5: cam belt slipped, timing retarded, compression at 1/2 spec, and well, valve will bend soon....

6: CEL glowing running? can be in limphome, limp cancels Idle controls (in may cases) RTM read the FSM on DTCs.



if fails hot?, is hot = 180F temp or more? "thermometer time"

if not, the PCM goes , quite nuts.

Dec 23, 2013 | 2010 Honda Civic LX

1 Answer

Idle speed valve


cold or hot. there are 2, on all suz engines (what transmission, 3sp,4sp or 5sp)
post symptoms, sure bad idle but hot , cold or both
hot means engine is at 180F or more holding......
is hot idle above 800 RPM or Below?
is the idle surging out of control hot?
Does hot idle (spec 800) drop in RPM with cab heat fan on and Headlights turn on at the seam time.? (yes, bad iSC funcition)
if ildle is low, say so, that is cause by other bad parts. (or set wrong)

Dec 11, 2013 | 1991 Geo Tracker

1 Answer

Increase then decrease idle when engine is cold especially


cold engine idle surge. (problem)
RPM range of surge not stated
300-700 or 800 to 1500? (range is critical to diagnosis)

bad fuel
running summer fuel in winter (running old fuel?)
needs a tune up bad, see the list in the operator guide.
idle speed controller,sticking or EGR valve same. (clean them)
location not stated, so cant guess about local air temps.?
no other symptoms, lack of engine power? etc?
was it ok last week, or better, when was the last time it was OK?
1week, 1year?
surge , causes, on a tuned engine might be:
1: too lean. so lean the ISC can not control idle. rpm low, stalling
2: too rich, flooding, stalling, spark plugs foul (look at them)
3: weak compression in 1 or more cylinders.
4: bad spark.
5: air leaks, in the plenum causing , ISC to lose control.
why high RPM?

especially?
well that means it fails hot too.
and there is a simple tests. for hot surge.
is engine fully hot? 180F and holds solid there?
say rpm is about 800
and you turn on head lights, heater fan and (not AC) and defrost.
the RPM must hold or the ISC is failing.
ISC -= idle speed controls. (all EFI has this function)

Oct 28, 2013 | 1996 Honda Prelude

1 Answer

P1481 p1484 fault codes?


For mini cooper
P1481 - is
Type Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled Description Fan Secondary Low With High Fan On Conditions
Cause Key on or engine running, high speed cooling fan enabled, then the PCM detected the fan secondary circuit was low (with the high speed cooling fan on).
and

P1484 -
Type Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled Description Open Power Ground to VLCM Conditions
Cause Key on or engine running, then the PCM detected that the VLCM power ground circuit was open.

hope i can help you, or you can ask the 24 hrs live technical support http://www.spobd2.com/service, they will like to help you, good luck

Aug 04, 2013 | Mini Cooper Cars & Trucks

2 Answers

Engine fan not working


Could be low on coolant, the cooling fan motor, a relay, or the fuse among other things.
A mechanic would check for power at the fan motor after checking the fuse.
Is the check engine light on ?

Jul 05, 2012 | 2006 Jeep Commander

2 Answers

Primary radiator cooling fan is not running. replaced fan motor. no change. connected with connector from other fan, fan made a few turns and blew the fuse. already replaced relays before replacing fan...


Now that you know that there IS a difference in the fans, try this....

It is normal for the A/C air to warm up a little when stopped. Less airflow thru the condensor. It is normal for the engine temperature gage to rise up to about the 80% mark on its scale before the cooling fan kicks on. The gage will also show about the same reading on the first start of the day, until the thermostat opens.

If the fan(s) are not working properly the A/C air and engine temperature will rise. If you have a belt driven clutch fan, the clutch may be worn out. All cooling fans kinda sound like miniature jet engines when its hot out, more so when the A/C is on. Replacing the clutch is all you can do for a belt driven fan. Electric fans are more complicated....
Check all main power electrical connections first.... Electric Fan(s) not working, Checking the fan(s), relay, fuse and engine temperature sensor's.
Verify that the fans work by unplugging them and run jumper wires to the fan(s) from the battery, and not from the other fan or anywhere else. If they run, your problem lies elsewhere. If either does not run, it's the motor.
Next thing to check is for power at the fan connectors. You have to be cautious doing this because the engine needs to be running and warm if not almost hot, and the A/C also needs to be on. (Both must be on and running for the duration of this checklist.) The A/C fan is on the passenger side and should come on almost the instant the A/C is turned on. It is also the secondary engine cooling fan and should cycle on and off in relation to engine temperature. Use a test light to probe the two wires on each fan. If you find power the fan motor(s) is/are probably bad. If there is no power to fans, roll up your sleeves!

The temperature switch is usually located above the oil filter. If the dash gage is working, its probably OK. Next is the Fan Control Temperature Sensor, located IN or CLOSE to the thermostat housing. You will find out if it is working later is this checklist. I just wanted you to know where it is. Next is the relays and fuse's. Usually located in the engine compartment on the passenger side power distribution box. You will need to remove anything over the cover to open it. If the fuses are OK, tap on the relays or pull them out and push back in. If the fans are still not running, pull a relay and probe the socket terminals for power. Two or three of the terminals should have power, usually criss-cross from each other. Two are hot battery power, and the third is the "signal" voltage which triggers the relay to send 12V battery power to the fan. This signal voltage comes from the sensor at the thermostat. If only two terminal's have power, then I would replace the thermostat sensor if not both sensors.

Hope this is clear as mud! and helps! Please let me know what you find.

Aug 28, 2011 | 2003 Pontiac Grand Am

2 Answers

Cooling problems


It sounds like everything is working properly. The temperature will go up when idling. The wter isn't being pumped through the system as fast. When idling, the engine runs at around 750 rpm's. When driving, even at low speeds, the engine speed is at least double that. Make sure your antifreeze is set for at least 20° below zero.

Aug 28, 2009 | 2002 Mitsubishi Lancer

2 Answers

When sitting at light car runs hot, when moving car stop running hot


At idle, with engine hot, is the fan blade turning?

Theory is, at idle, need the fan to pull air though the radiator, at highway speeds, the air flows through without need for the fan.

Aug 12, 2009 | 2003 Mitsubishi Outlander

1 Answer

My 2000 eclipse 2.4L runs hot at idle only


Your car should have a High and low speed connector there. That would cause the problem you described, if the PCM sees the temp at about 195 the low speed fan should kick on, if that fan doesn't provide enough airflow it kicks on to high speed to cool quicker. in your case the low speed is non existent and the computer is simply waiting for the temp to raise to the point where it triggers the high speed relay.

Feb 25, 2009 | 2000 Mitsubishi Eclipse

Not finding what you are looking for?
1994 Chevrolet Corvette Logo

Related Topics:

267 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts

yadayada
yadayada

Level 3 Expert

76649 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8518 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...