95 5.0 bogging/ hesitating SOLVED

Andresquintana.mma

Active Member
Nov 28, 2014
191
19
28
I bought a 95 gt 5 speed a few months ago and it ran great until recent. Didn't do any work to it but it started bogging out or hesitating recently. Sometimes when I cold start it will be bogging when I try and push the gas in 1st and will all of a sudden start running fine, then a few blocks later it will do the same thing. It doesnt matter what gear its in. The weird thing is when im driving normal and it bogs down i will floor it then it will pick up like its running how it should be. I thought it needed a tune up so did the spark plus and wires and the thought it was a fuel issue so I replaced the pump but no luck. Still running the same. I ran codes and didnt see anything that would cause that (dont remember the codes but I can pull them again if needed)
 
  • Sponsors (?)


If you're getting the same codes that keep coming back, you should fix those because they could be masking the actual problem. If you have any O2 sensor codes, then you probably have bad O2's. The computer ignores a lot of sensors when you mash the gas pedal (Wide Open Throttle, or WOT), so if the car seems to run fine at WOT then you likely have a few bad sensors.
 
  • Useful
Reactions: 1 user
Ok sorry its taken me so long but I was out of town and busy with the holidays. So I ran the codes and this is what I found

Engine off 11,17,32,33
Engine on 111, 4,12,17,23,33,32,21, and 16

Also when Im driving the car engine light isnt always on sometimes it goes away and will randomly pop up. To me it sounds like its misfiring I noticed the other day when it was bogging or misfiring the check engine light was flashing.Replaced the distributor last night and same problem. Has new plugs and wires along with a fresh oil change thats about the only work Ive done to this ca. Like Chythar said I got a code 16 which has to do with the o2 sensors Id say thats my next logical step?
 
You can continue to throw parts at it or be methodical and perform diagnostic procedures to fix this.
Do this list step by step, it explains how to diagnose efi engine running problems, pay attention to the directions because the 94-5 cars are a little different and that is highlighted
 
Ok so I was reading the codes all wrong I didnt know I the 94/95 were 3 number codes.
The codes I got are
engine off
172 o2 Sensor sensor circuit indicates system lean (right side)
176 o2 Sensor circuit indicates system lean (left side)
332 EGR valve opening not detected

engine on
412 Cannot control rpm during KOER high RPM check
116 ECT out of self test range 0.3 to 3.7 volts
172 o2 Sensor sensor circuit indicates system lean (right side)
332 EGR valve opening not detected

How do I fix the car running lean? Any leads to where I need to start would be great. My idle dosent surge or do I just start at the beginning of the list that General posted on here? The first thing it tells me is to pull the codes. Thanks in advance,
 
Do the list but most times the lean codes mean there is a vacuum leak.
Found a few missing vacuum hoses they are capped off. One on tps and one next to the fuel pressure regulator hose. I Believe a green hose goes to egr valve and a red hose goes to the other one but I can’t find where those hoses come from. I have them circled in the picture below thanks
991C2AEF-BF9F-4491-8C73-5DCC7D5A035A.jpeg
 
I had a similar issue with my '94 Cobra last winter, turned out to be rotted vacuum lines. My understanding is when you go WOT vacuum pressure cuts out, so you won't be sucking it air and lean condition goes away. I think.

Found a few missing vacuum hoses they are capped off. One on tps and one next to the fuel pressure regulator hose. I Believe a green hose goes to egr valve and a red hose goes to the other one but I can’t find where those hoses come from. I have them circled in the picture below thanks

you are correct on the green/red hoses. I'm in the process of replacing mine - they were brittle and snapped when I was replacing the EGR valve. Here's some pictures of where they lead to on my '94 I'd imagine the '95 is very similar. Note my air intake is off in these pictures.
First picture is the junction they head to, normally sits under my CAI (I've pulled it out of place to get the picture)
20210207_131414.jpg
Second picture to show where that third hose leads to, not sure what that is.
20210207_131422_HDR.jpg

Now with it lying properly, you just barely see the green & red lines going under the fuel lines then the throttle body, from there they run back along the valve cover

20210207_131537.jpg
Picture of where the red line comes out from under the EGR (green one should be in the sheath with it but is MIA right now)
20210207_131603.jpg
Sorry for the bad MS Paint work, but I've outlined in blue where that line heads in the fender after the junction
20210207_132435.jpg

If you think it would be helpful, I do have older pictures when I had that passenger side fender off, showing where the lines head to under there, but the pictures weren't taken for that purpose so its a little jumbled. Hope this helps - and if anyone has advice on sourcing replacement lines and shielding material, I'd appreciate it. Haven't looked into it yet.
 
  • Like
Reactions: 1 user
Bro you are awesome. I guess previous owner burnt them or they touched the header and they just got shoved inside the fender! Are you running smog pump? Mines on there but nothing is connected to it. Is that what that the pinkish line and white line on yours running to? I think for now I'm just going to have to run a regular black hose to them until i can find some replacements.
IMG_20210207_131003.jpg
 
Update all is fixed. No check engine car runs beautiful. Ran a ton better with the vacuum lines connected in the right places but still had check engine and running lean on right bank. Swapped the o2 and fixed everything. Thanks for all the help.
 
  • Like
Reactions: 1 users