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Searched, diagnosed, everything.

Messages
108
Likes
89
Location
St. Louis, Missouri, USA
#1
So my fiesta, last winter driving in light snow it suddenly had a wrench light and limp mode. Like the bypass valve doesn't operate, runs a bit rough, on cold start for A few min, cannot get into boost more than a few lbs before the car cuts out. . I did a ton of diagnostics and replaced a bunch of stuff myself. Boost control solenoids. Lines, replaced aftermarket bypass valve with a new OEM. Replaced other sensors like iat and a few things. I got bit on hand/end of wrist by a brown recluseand it was a severe invenomation. So my left hand has been out of commission and still isn't 100 after surgery, skin grafts, etc. so I haven't been working on cars. I sent it to a shop and they replaced the entire wiring harness and. Some redundant stuff I already did replacing solenoids and a few sensors. Still no luck.

I'm about to dump the car. I've searched, researched, etc. so I apologize for making a common post. But I need ideas or I'm dumping the car wholesale. Engine compression and leak down were basically perfect. Mods are LSD, big brakes front and rear, I forget the turbo and manifold upgrade, lol, but it's a common 300hp pump gas turbo. Every supporting mod. Port injection. Etc etc. common stuff, nothing special. No shortcuts on mods or build. Always maintained properly.

Thanks in advance if you can help. I'm sorry for not giving a bunch of specifics, but like I said, this car has basically sat in the garage for over a year and only started regularly and idled to heat cycle and moved to do oil changes and stuff. I just don't remember all the work and diagnostics I performed exactly chasing this. But I've basically looked at everything I could find related to these symptoms.
 


OP
Saponetta
Messages
108
Likes
89
Location
St. Louis, Missouri, USA
Thread Starter #2
Having an access port tune loaded but the access port unplugged doesn't cause an issue does it? I've ran the car like that most of its life. Never had an issue.

Car has 61k miles, bought new. Did have engine replaced at 600 or 700 miles because of an oil pressure issue. But that shouldn't be relevant. Done by Ford under warranty and not an issue since till the current problem.

Only check engine ove ever had is twice for it and it was replaced. I'm a bit suspicious of this to be honest, that I've had a reoccurring issue the last year before the wrench light. But it's been replaced....

I spent 4k and months at the shop and it was pointless. I'm friendly with the owner from growing up, and he even got a Ford tech to come moonlight on the car and try to get to the bottom of it.

I'm going to dump this thing and get a gr Corolla or sell out Mazdaspeed Miata also and get a new boxster. About done.

Thanks for listening to my rant and for your time and knowledge.
 


dhminer

2000 Post Club
Messages
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3,167
Location
Burlington, NC, USA
#4
Damn, crazy about the spider bite. Sounds like you’re lucky to still have your hand at all.

You’re correct the accessport being unplugged is not an issue.

Have you checked the low side fuel pressure sensor? What codes are present?
 


OP
Saponetta
Messages
108
Likes
89
Location
St. Louis, Missouri, USA
Thread Starter #5
sorry for long reply. this is a 3rd car and it's just been on the back burner. has codes for iat sensor that has been reoccurring for a long time before this happened and replaced numerous times. code for bypass valve, boost control solenoid, map sensor. wrench is always on. could it be the aftermarket maf housing? I haven't boost leak tested the car ...but my intercooler piping is so tight to the oil filter I have to remove the lower hot pipe to change oil, I've had it blow off once and the car was obviously without boost, but no wrench or limp mode so I didn't think it was a boost leak. the car also likes to idle rough when filling the fuel tank which I believe started when this issue came up. it doesn't have a code related to the fuel system or evap....so...m.andny help would be appreciated. thanks in advance. sorry I don't have specific codes up here ...it's 5am , raining and I don't want to go write them all down again at the moment. thanks .
 


dhminer

2000 Post Club
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3,167
Location
Burlington, NC, USA
#6
Gonna ask the real stupid question. Did you accidentally use on the fly map switching to put the tune on the wrong map slot? I wouldn’t think that’d cause these issues but my car went haywire when I switched to the AEM MAP sensor and the tube’s voltage parameters weren’t adjusted.
 


Grsemky

Active member
U.S. Navy Veteran
Messages
542
Likes
442
Location
Arizona
#8
sorry for long reply. this is a 3rd car and it's just been on the back burner. has codes for iat sensor that has been reoccurring for a long time before this happened and replaced numerous times. code for bypass valve, boost control solenoid, map sensor. wrench is always on. could it be the aftermarket maf housing? I haven't boost leak tested the car ...but my intercooler piping is so tight to the oil filter I have to remove the lower hot pipe to change oil, I've had it blow off once and the car was obviously without boost, but no wrench or limp mode so I didn't think it was a boost leak. the car also likes to idle rough when filling the fuel tank which I believe started when this issue came up. it doesn't have a code related to the fuel system or evap....so...m.andny help would be appreciated. thanks in advance. sorry I don't have specific codes up here ...it's 5am , raining and I don't want to go write them all down again at the moment. thanks .
I haven't done the EVAP fix for mine yet and will get rough idle after fills but no codes, but it clears up after a few miles of driving... You might have some broken wire, I would start checking continuity between connections since swapping parts hasn't yielded fruit
 




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