Question about 1990 Jeep Wrangler

2 Answers

Engine blowing oil from oil filler cap

1990 jeep yj 2.5L engine blows oil from under oil filler cap. when I remove the cap while engine is running it lets air out.appears to be building back pressure. replaced pcv no help. big oily mess under hood. engine does not smoke the usual blue smoke if rings were bad also dosen,t smoke when cranked after sitting over nite.

Posted by on

2 Answers

  • Level 1:

    An expert who has achieved level 1.

    Corporal:

    An expert that has over 10 points.

    Mayor:

    An expert whose answer got voted for 2 times.

  • Contributor
  • 1 Answer

I had the same problem. I changed the pcv valve and checked the hose. It still did the same thing. Then I checked the metal tubing that the hose connects to and found it was full of hardened gunk. I sprayed PB Blaster into the tube let it soak for awhile. Then took an old choke cable, put it on a drill and ran it into the tube like a drain snake. It took a while of doing this over and over but eventually got it cleared out. Now, no more oil all over the engine and hood compartment.  

Posted on Mar 21, 2009

  • 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.

    Hot-Shot:

    An expert who has answered 20 questions.

  • Expert
  • 58 Answers

If you have changed the pvc valve with no success you should check the breather hose to the manifold. Also check that the hole is clear in the fitting on the manifold that the hose goes onto. Failing that its most likely the rings I'm afraid. A cylinder leakage test would be the best way to check this but is specialist equipment. No more than 15% leakage is normal

Posted on Dec 12, 2008

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Blow back through tappet cover


blow back through the oil filler cap while engine is running is normal

4 cyl or the V6 engine

causes
using /burning oil would be worn rings
oil seal leaks
hardened valve stem seals
faulty egr valve

Jul 28, 2016 | 1998 Toyota Camry

1 Answer

I have a problem with oil blowing back through the dipstick in my 1994 Jeep Wrangler YJ 6 cyl engine... I have built a few engines of various types over the years and have done all my maintenance all my...


No solution from me, Note: Sounds like your pretty familiar with the Positive crankcase ventilation (PCV). You said the valve is pulling a vacuum I am assuming it is from the intake manifold side correct? With the PCV was working sure seems like it would keep the oil from coming out of the dipstick tube. I am stumped as well, sounds almost like too much blow by from the cyclinders you already stated that with the possible broken compression rings?

Dec 08, 2013 | 1994 Jeep Wrangler

2 Answers

Astra 1,7 cdti


yeah, it's supposed to do this, so keep the cap on when the engine is running

Oct 21, 2013 | Cars & Trucks

1 Answer

What will cause a blow back


there will be,if it shoots the cap off while you are unscrewing it then you might have an issue,but oil will come out with car running and cap off

Nov 13, 2012 | 1991 Toyota Camry

1 Answer

1990 yj 2.5 blowing cold air no heat what could it be


check for low coolant in the radiator.this is usually the most common reason. not running hot?also it could be a bad tharmostat in the engine.this maintains a constant temerature in the engine. if this does'nt help,please repost your question and we'll be happy to help.thank you for choosing fixya.com

Nov 29, 2010 | 1987 Jeep Wrangler

5 Answers

Oil coming out of engine oil filler cap even though i have changed oil filler cap


The engine breather pipe seems to be blocked.
It may also damage the oil seals.

Oct 27, 2009 | 1992 Volvo 940

2 Answers

Its blowing oil out of the oil cap why would this be ?? also i bit of white smoke then came out the back


The oil level may be too high.
Is the filler cap tight?
blow-by in the cylinder piston rign area. A wet test of engine compression will detect this.
A bad had gasket. Engine will be over heating as water is being used up during combustion.
Bad head gasket. Could explain white smoke in exhaust.

If the engine is overheating I would be suspecting a problem in the head area.

Good Luck. SnugglePants

Oct 26, 2009 | 1988 Mitsubishi Galant

1 Answer

How to change oil on 90 nissan maxima


Park the car on a level surface, let the engine warm up, Locate the engine-oil pan under the car, and remove the drain-plug. Put a container under the oil-pan to collect the old oil. Remove the oil-filler cap on top of engine head-cover. Remove the oil-filter by the engine block. You could grab it with one hand and turn counter-clockwise. While waiting all oil to drain out, smear some new engine oil on the new oil-filter 'o'-ring, and screw it back in place. Tighten 3/4 turn after the o-ring hits the engine surface.
Clean the drain-plug with a clean rag and tighten back in place-not over-tighten it!. Put back about 3-quarts of new engine oil through the oil-filler cap, and hand tighten the cap. Start the engine and look for leaks. After a few hours later, check the oil level. You are done!

Sep 26, 2009 | 1990 Nissan Maxima

2 Answers

1990 YJ JEEP WRANGLER


the motoor is having trouble breathing pcv may be clogged check all breathers clean as needed or its over filled

Jun 21, 2009 | 1990 Jeep Wrangler

3 Answers

1990 Jeep YJ 6 cyc. Won't Start---No Spark From Coil


It would be great if you could find the Ignition Control Module!!! From my experience on my Jeep...90 YJ 4.2 liter carb. it does not have one...Computer controlled only...

May 17, 2009 | 1990 Jeep Wrangler

Not finding what you are looking for?
1990 Jeep Wrangler Logo

1,100 people viewed this question

Ask a Question

Usually answered in minutes!

Top Jeep Experts

yadayada
yadayada

Level 3 Expert

61249 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21949 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6812 Answers

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

Answer questions

Manuals & User Guides

Loading...