Backfiring into intake, timing issue?

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SHOdded

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do you mind listing brands of the replacement parts used so far?

most threads have listed some type of grounding issue with ignition system components as a culprit with backfiring into intake/ hard start / no start.

at least one noted water in the plugwells after an engine wash, so basically another electrical issue.

haven't seen egr listed as a root cause, but can't hurt to check/clean the dpfe and the egr "nostrils".
 

Dylpro

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do you mind listing brands of the replacement parts used so far?

most threads have listed some type of grounding issue with ignition system components as a culprit with backfiring into intake/ hard start / no start.

at least one noted water in the plugwells after an engine wash, so basically another electrical issue.

haven't seen egr listed as a root cause, but can't hurt to check/clean the dpfe and the egr "nostrils".
The DPFE is brand new, if I’m not mistaken it was Walker. I’ll have to go back and check what the brands were for everything but here’s what’s off the top of my head

DPFE: Walker
Plugs: Motorcraft
Plug Wires: NGK
O2 Sensors: NTK
CPS: Delphi
CKP: SHO Source
Vapor Canister: Carquest

Those I believe are all the parts that would be anything related to my issues.

I haven’t tried anything with the EGR as of yet. I broke the green line that goes from the EGR to the solenoid and replaced it with some tubing of the same size, though I need to get another line as I cut this one a little short. My next step was going to be attempting to clean, if not then replace the EGR.

I work today but am going to try getting some testing and further investigations when I’m home and will report back

Also discovered last night that my CEL is burnt out, after wondering if any of these codes would cause it to come on, foolish of me not to check if it was coming on when turning the ignition from the start. Whether or not this was intentional by the seller at the time I suppose I’ll never know
 

BaySHO Performance

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I've never known a malfunctioning EGR system to cause the symptoms described.

Test the EGR valve first if considering replacing it: take the small tube off the back of the EGR valve. Attach a tube of the same diameter to the valve and suck on it. You should hear the diaphragm in the valve opening and closing. Now, turn the engine on and do the same thing. If the nostrils are blocked, the engine revs will stay the same. If the revs go down, the nostrils are clear.

Take the throttle body off, and you will see four holes in the intake behind it. Top two for the IAB, Bottom two for the EGR. If these are blocked, typical codes point to EGR valve opening not detected, or insufficient EGR flow. Unblock the nostrils with carb cleaner and a pick.
 

Dylpro

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Writing this as I wait for the tow truck from AAA. Car started without issue today and decided to get gas about 5 minutes from my house. Go to start it after filling up and the starter won’t engage, walked the five minutes home to get a Jack and small hammer and next try it begins freewheeling nonstop. Pulled the negative cable as quickly as I could but it was stuck on for at least 10-20 seconds. Is my flexplate more than likely damaged from this?
 
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BaySHO Performance

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If the starter was spinning freely it won't have engaged the flex plate and damaged it.
I just had to replace an MTX starter for this very reason: spinning freely without engaging the flywheel. Got progressively worse until I almost got stranded. The electromagnet has got too weak. A replacement is necessary.
 

Dylpro

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Yeah no grinding or any nasty noises aside from the freewheeling so hopefully caught a break then.

Starters less than 3 months old, this was also a remanned Carquest starter which I’d heard can be hit or miss with quality. Going to order a new starter, any recommendations? I was recommended BBB industries by my boss previously, going for new rather than reman this time as well
 

Dylpro

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Thanks for all the help so far everyone. I’m wondering if the issues I was experiencing with starting may have just been rooted in the failing starter, we’ll see once I get the new one on how it goes.

Decided to take this time to address the leaky oil pan gasket as well so won’t be up and running for at least a few more days anyway.

Debating on whether or not I should go ahead and do the rod bearings at this point as well. I see it’s something mentioned more for MTX cars but is it still worth doing for peace of minds sake? Car has a little over 135k on it
 

BaySHO Performance

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How many miles on the car? If above 150K I would at least check them. Look at the top bearing which gets more wear than the bottom one. If copper is showing, replace them. Available from SHO Source.
 

Dylpro

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Hello all, a long while between updates, but after 2 years of relative “stress” free ownership, I’ve been spending a lot of time messing about trying to get some nagging issues still resolved.

Since my last post I did change the rod bearings (just in time it would seem after seeing the post regarding their supply issues), though it seems like I did not get a good seal on the pan as I’m still having a fairly noticeable leak. Will soon attempt to redo the pan gasket to hopefully rectify this.

My larger issue at hand still seems to be related to the original issue that plagued the car when I started this thread.

The car starts every time without fail, although it’s still typically a rough start up, especially when starting cold. Once running it stays running, drives well, no real noticeable issues. It’s served it’s purpose as a vehicle to get me from A to B for 2 years now.

Unfortunately the car feels far from running smooth. I’m still being plagued by codes 332, 558, and 565. I’ve replaced the DPFE, EGRV Solenoid, and CANP solenoid to no avail. There’s also a fairly noticeable ticking noise at idle that from reading other threads sounds like it could be the chain tensioner perhaps? Not entirely sure. The car still smells like it runs extremely rich and I’ve noticed fuel seemingly leaking around the fuel line connections, as well as a general exhaust leak that I haven’t traced.

In complete honesty, I feel like I’m at a bit of a loss here and I decided to ask for some general thoughts and tips on what to chase down next on a laundry list of issues.

I’ve attached the photos here that I’ll try to give a brief breakdown of why I’ve attached them and will upload a video soon as well to try capturing the ticking noise I’m hearing.

The fuel lines: Obviously the leaking and strong gas smell, in the past I’ve noticed a gas leak coming from the attached union bolt on the fuel rail. Could the rough starts and excess fuel being dumped during that potentially be causing this fuel leak? After tightening the bolt a while back it stopped leaking from there, but now it seems it’s started to leak from there fuel lines. All of that said, I’m not noticing any drastic fuel economy issues.

Vacuum line from TB to CANP: I’ve been attempting to track down any potential vacuum leaks and I first replaced this line when I originally had the intake apart, though I could hear a noticeable hiss from it recently. Decided to replace it after discovering it was not the correct size, but the hissing noise remains. If I pinch this line it stops, almost exactly as the line that was on previously would do, but there’s no noticeable damage anywhere on the lines. I also recently replace the TB gasket thinking that could have been the issue, but the hissing is definitely coming from this line.

Finally, the last two pictures is a line I noticed that was broken just about a day ago. If I’m not mistaken it looks like it goes to the Evaporator core at the firewall. At first I thought it was the line breaking off from the vacuum T at the bottom of the CANP solenoid but I’m not entirely sure. I’m looking at anything that could help solve some of these issues so again, just attaching for the sake of finding things wrong.

Any help, tips, advice, anything at all is greatly appreciated! I can try to update some of my other tests/findings I’ve done through the past 2 years as well, but I was attempting to (though failing) to keep this relatively brief lol
 

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BaySHO Performance

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Not related to your problems, but you might want to put a fresh coating of heat sink grease on the back of the DIS to stop it overheating and breaking down.
 

Dylpro

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Not related to your problems, but you might want to put a fresh coating of heat sink grease on the back of the DIS to stop it overheating and breaking down.
Want to say that I did so back when I originally disassembled the intake and had spent some time messing about with it but better to air on the safe side and do so

Here’s a video of the car running with the noticeable tap-tap-tap at idle

On a side note, looking around for junkyards by me I found an extremely clean, seemingly untouched ‘93 base model, any parts that are worth going back for that interchange? I snagged the driver side door panel to replace mine that would fall off anytime I shut the door

Edit: Found the fuel line leak, tiny nick in the line just back of the connector, might try just using a union and see if it holds before going about replacing the entire line
 
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