Question about 1987 Chevrolet R30

1 Answer

Truck runs good for awhile then service engine light comes on and it runs like **** for awhile and then the light goes off and it runs good again, what could be my problem ?

I've changed the map sensor, the engine coolant temperature sensor, idle air control valve motor, and the throttle position sensor with no luck.

Posted by on


1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that got 5 achievements.


    A rookie expert who has answered 20 questions on their first day.


    An expert who has answered 20 or more questions within one hour.

  • Expert
  • 71 Answers

Check the spark plugs wires

Posted on May 09, 2014


6 Suggested Answers

  • 2 Answers

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

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.

Posted on Jan 02, 2017

  • 12 Answers

SOURCE: 1994 s10 service engine soon light

Have you had the truck scanned for codes? If so, what was the code, codes? Why did you replaced those listed parts. Can you hear any hissing noise coming from the engine or engine compartment?

Posted on Sep 04, 2008

  • 359 Answers

SOURCE: 90 chevy 5.7L k1500 failed emissions


Posted on Nov 27, 2008

  • 4669 Answers

SOURCE: 87 chevy truck with TBI idles too fast

Spray the intake with carb cleaner to find the vacuum leak. Check where the EGR mounts and the throttle body gasket sense you had both off.

Posted on May 10, 2009

  • 1486 Answers

SOURCE: 1987 chevy S10 engine idle problem

relace the throtle air idle valve.The temp switch will allso cause this problem.

Posted on Jul 19, 2009

  • 1050 Answers

SOURCE: I have a well kept 91' Chevy Caprice V8 5.0L TBI.

It's very common for these engines to develop a vacuum leak around the base of the throttle body. You can check for this with a stethoscope or a can of aerosol carb cleaner. Also, IAC valves are a common problem, but easy to clean before you replace it. Remove it and use the carb cleaner and a brush to remove the build up, also the crud inside the IAC orifice. Next clean the throttle butterfly valve and throttle bore thoroughly with carb cleaner. If this doesn't help, remove the egr valve and try and poor a little paint thinner through it when you're holding it upside down, it may weep a little through the pintle but it should not obviously allow the paint thinner to flow through. If all of this fails to help, you'll have to get your hands on a scan tool and read IAC counts at idle to see what the computer is trying to do. If the counts are high...above 50, the computer is trying harder to open the IAC to keep the engine running because of some kind of problem, usually mechanical. If the counts are very low...below 5, the the computer may be trying to counter a vacuum leak that is providing most of the idle air, which is unstable and can cause the stall.

Hope this helps.

Posted on Jun 21, 2010

Testimonial: "I added more comments for the first poster but maybe you can put your second though also. I checked the EGR and took it off for a closer inspection, also took out the IAC cleaned it with rag with some solution and brushed it. My question is, how far out should the needle be or how can I tell when the IAC is warn out. thanks ."

Add Your Answer

Uploading: 0%


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



Related Questions:

1 Answer

3.3l auto. Battery light comes on every morning?

When you replace your alternator do you disconnect your positive cable on your battery right
Maybe the problem is you battery now
Disconnect your + cable from your battery and conected again make sure all your wireless are connected I hope that helps. Good luck

May 11, 2016 | 2007 Chrysler Grand Voyager

1 Answer

Help. check engine light comes on also yellow open end wrench light comes on.

Have you had the engine computer checked for trouble codes ?

Sep 05, 2015 | 2005 Lincoln LS V6

1 Answer

How do you reset the service engine soon light

Put the key into the ignition and turn it to "Run." Don't start the engine. Press down slowly and fully on the gas pedal, then release it. Do this three times in five seconds. Watch for the "Service Engine Soon" light to start blinking. This indicates that the system is resetting itself. Turn the ignition to "Off" and wait one minute. Start the Century's engine. The Service Engine Soon light will flash for a moment, then turn off. If it doesn't do this, repeat the process.if all else fails...Disconnect your battery for one minute and then reconnect it again that should reset it, if the problem that you have in your car is still there then that light will come on again after whille then you gona need to run diagnostics on your car to find the problem if it will not come on again then that should take care of it.9-08-2006Let me tell you about my experience with my 1995 Buick Century.When my buick sits for a while while running, the radiator fan comes on, you know?Well, after the fan does its thing, SOMETIMES the "SERVICE ENGINE SOON" light comes on.THEN.....when this happens again, it may take a couple times of after the fan comes on, then....the light goes off !!!Its like it needs to go thru some sort of "CYCLE" , THEN THE LIGHT GOES OFF...Who knows though,you may have LEGITIMATE problems with your car.good luck.

Aug 17, 2014 | 2003 Buick Century

2 Answers

Service engine lights comes on for awhile and goes off. Checked with encode tester and recieved Bank 2 sensor 1 o2 sensor. Is this a for sure bad part? 2003 Mistubishi Diamante LS V6.

You typically would like to do further diagnosis, however on these cars, the Denso sensors are very common to fail, and are the cause of the light 99% of the time, especially if it is the only code set.

Bank 2 sensor 1 is located on the top of the exhaust manifold on the radiator side of the engine. You will need an O2 sensor socket or a small 22mm wrench to remove it

Oct 20, 2009 | 2003 Mitsubishi Diamante

1 Answer

95 contour 220.000k 4cyl 5 spd temp gauge goes over half and check engine light goes on almost instant but i still drive and temp goes down for a bit and light goes out only when i turn engine off and...

Coolant sensor may be the problem. It is located near the thermostat housing. It may be sticking between modes & not operating properly.Also make sure coolant is circulating in system.

Sep 09, 2009 | 1995 Ford Contour

1 Answer

1994 Mazda B4000 4WD V6. Check engine light on. Truck

if i remember right if the battery light and check engine light is on, your alternators may be bad. your battery may just have enough to keep it running for a minute or so. you can take it out and get it tested at a auto parts store. or try charging your battery for awhile and see if it stays on longer. if this is completely wrong let me know

Apr 08, 2009 | 2007 Mazda B4000

1 Answer

Car dies when driving,check engine light comes on.

There is a good chance it could be your fuel pump , however if the check engine light is coming on and the dealer cant tell you what is wrong , try a different dealer or another shop. Second opinions never hurt.

Dec 12, 2008 | 2002 Kia Optima

Not finding what you are looking for?
Cars & Trucks Logo

51 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts


Level 3 Expert

76630 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8516 Answers

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

Answer questions

Manuals & User Guides