Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

missing


  Email This Post



TammyPulliam
Anonymous Poster
tpulliam@spsmail.org

Jun 17, 2009, 6:34 AM

Post #1 of 3 (2020 views)
missing Sign In

I have a chevy llumina 1991 six cylinder 3.1 engine. It is missing when I back up and when going up a hill. It feels like it is not getting enough fuel and shakes badly. The spark plugs and wires have been replaced. I thought there might be a problem with the 5th cylinder but the pressure reads 180 in each cylinder.I've misted wd 40 over the manifold to check for a vacuum leak and did not see any bubbles. I'm getting ready to replace the fuel filter and then I'll try the coil pack and the sensors. The engine light is not on so I can not get a engine check to find the problem. Does anyone have any advice?


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jun 17, 2009, 7:23 AM

Post #2 of 3 (2016 views)
Re: missing Sign In

I'm not sure what your trying to do with the WD40. Vacuum doesn't make bubbles, it sucks in. You use carb cleaner and listen for the engine to change RPM to indicate it's burning the carb cleaner.

You could very well have a bad coil pack but at this point you haven't even determined what cylinder is missing, never mind that it's an ignition problem. You really need a way to check the spark under load, possibly using a spark tester and power braking.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Sidom
Veteran / Moderator
Sidom profile image

Jun 17, 2009, 3:02 PM

Post #3 of 3 (2005 views)
Re: missing Sign In

Hammer has some good advise. Being a 91 it's OBD I, so the comp isn't as much help pinpointing the prob. Check spark as advised, if you have a fuel pressure gauge, take a reading. Running you should be between 30 & 40 lbs psi. As far as the coil packs, you could go old school & pull a wire off, put a old plug in it, set on the manifold (or any good ground, just not the battery) & fire up the engine, if it doesn't spark you probably have a bad coil pack.

Just curious why you thought you had/have a problem with #5 cyl?






  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap