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









Search Auto Parts

Intermittent no start


  Email This Post



misfitlife
Novice

Jun 10, 2021, 3:47 PM

Post #1 of 11 (334 views)
Intermittent no start Sign In

I Bought a used 2007 mazda 6. A month in went out to run errands car would not start their was no sound when I turned key over & I got no dashlights upon 3rd attempt to start dashlights came on 4th attempt car started. The key fob was cracked & being held together with tape. It was suggested the vehicle might be going into anti theft. I purchased a new key from the dealer & thought everything was solved then two weeks later the same issue happened again. Since then it's been back & forth with a random one or two moments of not starting then starting & seemingly running fine again.

battery & alternator tested good only code that came up was a bad 02 sensor


I Took it to mechanic for them to look at every time by they attempted to start it, it started. They said until it stalled they would not be able to determine what was going on. Any suggestions or ideas on what might be causing it? I am afraid of it ceasing to start entirely. Frown


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jun 10, 2021, 4:54 PM

Post #2 of 11 (324 views)
Re: Intermittent no start Sign In

It sounds like a connection problem somewhere. What the shop told you is true. You can't fix what isn't broken.

The best advice I can give you is wait until it happens again, then turn the radio up real loud and leave the key on. They go under the hood and start moving wires and cables around while listening for the radio to come on to tell you that you have hit the right wire.

I don't think the key fob had anything to do with it.



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

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.



misfitlife
Novice

Jun 11, 2021, 1:04 PM

Post #3 of 11 (280 views)
Re: Intermittent no start Sign In

Had 02 sensor replaced. They ran codes again & it's now showing an intake motor control valve sensor code. They could replace that sensor but they it might or might not be what's causing the issue. I have already put a lot into it the car & at this point am limited financially on what I can do. I am worried of going somewhere & finding myself stalled entirely. Researching the control valve I read that a bad valve could cause the car to stall and take numerous trys to start.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jun 11, 2021, 1:09 PM

Post #4 of 11 (276 views)
Re: Intermittent no start Sign In

That is definitely NOT what is causing your problem.



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

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.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jun 11, 2021, 2:27 PM

Post #5 of 11 (267 views)
Re: Intermittent no start Sign In

Back to what Hammer Time said first. If it does NO LIGHTS when not starting I/we take that as not a sound of trying to start?

An O2 sensor wouldn't do that so find the problem connection. Many cars load a lot of things right at battery it all needs cleaning up. Both cables clean with any other things right there first.
If no change follow each Bat+ to starter and Bat - to engine blocks or may need to replace an end properly spliced in?

The behavior understood by me is just exactly that weak connections get hot and be intermittent just like this,

T



misfitlife
Novice

Jun 12, 2021, 11:18 AM

Post #6 of 11 (243 views)
Re: Intermittent no start Sign In

02 sensor was replaced. When they cleared the codes & ran again the intake motor code valve disappeared. The cables & sensors look clean upon inspection but I am going to go ahead & clean them.
When I bought car I had to replace the battery & replace the terminals were loose. Had a friend replace them. He said it was tough as their was not a lot of cable to work with. I am wondering if he cut the wires to short & their not 100% making connection.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jun 12, 2021, 1:10 PM

Post #7 of 11 (234 views)
Re: Intermittent no start Sign In

Odd but it's not "looks" it's clear they don't make the connection. If already did ends they might have been the cheaper kind, two bolts squish bared wire.

Too short may be pulling on those. That type, if so is meant for emergency use not to leave on it.

About all parts outlets, here oddly check out Walmart's cable and good cable ends. Pre-made eyelet ends can get way too long and use what you need.

Brass and or real copper is much more cooperative to splicing and soldering your splices. If not doing that some alternatives are better than others.

Back to when I said "HOT." A tiny area that actually connects will get hot, burning hot and make or break the connection WHEN you try to start it.

Taper of top posts should be brushed up with a wire brush made just to do that new battery or not.

IMO avoid zinc for things exposed pay for the better stuff and do it right. At worst your car is better off for it - OK?

T



misfitlife
Novice

Jun 12, 2021, 4:08 PM

Post #8 of 11 (225 views)
post icon Re: Intermittent no start Sign In

Tried to upload photos to my post but no luck. Below are photos of both terminals my concern is you can see the copper wires sticking out between the terminals. Don't recall ever visibly being able to see the wiring on any terminals before.
I am going to clean the terminals as well as the sensors suggested.
https://sleepandlattes.files.wordpress.com/2021/06/20210612_123134.jpg
https://sleepandlattes.files.wordpress.com/2021/06/20210612_123623.jpg


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jun 12, 2021, 8:52 PM

Post #9 of 11 (208 views)
Re: Intermittent no start Sign In

Pics can be a pest here, to me anyway.

Those type terminals for repair are (I thought) marked for temporary or emergency use) but look like they would be working.

Those are NOT end splices to count on. You could test those now with a DVOM, WHEN problem is happening to see the current drop from bat post to the stranded wire and again on to the other ends.

Intermittent they may show fine it's being a pest on you.

To me they look too tight meaning pulling on cable I'd toss those for better ends anyway - said that before.

When more is known done right then will be easier to zoom in on what else if not those is causing this - that type do and do NOT look good but temporary already beat on that,

T



Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Jun 13, 2021, 3:31 AM

Post #10 of 11 (203 views)
Re: Intermittent no start Sign In

Or you could just do what I suggested in the first place. Just wiggle wires around until you see a response.



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

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.



Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Jun 13, 2021, 5:38 AM

Post #11 of 11 (196 views)
Re: Intermittent no start Sign In

More I hear of Hammer's trick/way I like it better. Can do that alone. Leave door open with interior lights start the wiggle test right at those. It would snap to work for radio- lights anyway. Move on and wiggle away at starter and engine block ends. Starters are the big draw not done yet. If it's better and doesn't start but clicks and tries get the dang right cable ends,
T







  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap