As the title states, I'm in need of some help! I'm going to go through the whole process of what I've done on the car, how it was when I got it and the progression I've made...now I'm stumped as to what could be causing my issue(s) 
.
My main issue on the car is that it will not accept full throttle; it bogs down and backfires. I've been tinkering with the car for the past month, made some serious progress, but still not 100% right...bear with me everyone, this may get lengthy, but I'd really appreciate a thorough read and some thorough responses, if at all possible.
I obtained the car about a month and a half ago; was told that the fuel pump was bad. So I started there...that didn't fix my issue; I was having to start the car by fooling the ecu (put my thumb on the ICV and plugging in the hose leading to it from the intake boot right as the car would crank). Yes, I've checked for vac leaks, inspected all of my hoses and connections. Here's a list of everything I replaced and what it "solved":
valve cover gasket: did nothing
In tank fuel pump: fixed nothing :???: car still wouldn't start, the one time it did, it shut right back off
Fuel filter: ^^
(both of these parts above ^^ were from advance auto)
checked for spark and all 6 plugs were sparking normally
ICV: fixed sporadic idle after start up; car still didn't start on it's own (came off of a lower miles '87)
mass air flow meter: Again, idle was better, accepted slight throttle, but car still didn't start on it's own
cold start valve: car would start but then shut off, eventually the car wouldn't even start on it's own; car wouldn't accept full throttle
I suspected that the fuel pump wasn't putting out enough pressure, so I took back my advance auto pump and bought a used one out of a 1986 325es
(the icv, mafm, csv, oil sensor, and fuel pump all came off of the same parts, a 1986 325es)
At this point the car still wouldn't start on it's own..so I moved to the coolant sensors; I replaced every coolant sensor. The one that made the biggest difference was the coolant sensor with the two female connectors (not sure how to describe it, but it's the one on the very top of the thermostat housing with the two prongs sticking up...forgive me if that sounds ignorant :???:)
The car would then start on it's own, but would run for a little then bog down and have an oddly low idle, but could be driven and started after about 3 times turning the car over.
The next morning I went to start the car and it wouldn't start, I attempted to fool the ecu by doing my thumb trick on the icv..car still wouldn't start...eventually after about 20 minutes the car started but shook profusely! I shut it off and checked my SPARK PLUGS! They were completely, COMPLETELY gone...so I bought bosch replacements and the car started up and idled fine, but still wouldn't accept full throttle and would start on it's own consistently.
From there I checked my ecu; there was slight corrosion, so I replaced it with an ecu out of another 1987 325e. The car started on its own some-what easier, but was still finicky while driving and wouldn't take to full throttle. If you ease slightly into the throttle the car revs up fine, but if you punch the throttle, it would bog down and shut off.
Fuel pressure regulator: changed nothing
Fuel rail and injectors: tried a different fuel rail and injectors; car wouldn't even start, so I went back to my fuel rail, cleaned my injectors, and replaced a few o-rings, and the car started up slightly easier than before, but still wouldn't take full throttle
I then drilled a hole in my tps to allow oil to allow for oil to drain out and cleaned it with brake cleaner...that helped my idle slightly, but nothing else.
Here's a brief recap of everything I had done up until tonight so we (I) don't get lost in my own thoughts: icv, mafm, csv, drilled a hole in the tps, all coolant sensors, valve cover gasket, injectors, injector o-rings, fuel rail, fuel pressure regulator, fuel pump, fuel sender, fuel filter, spark plugs, checked for spark, and changed ecu.
Tonight I went to my buddy's shop tonight and we searched, did "diagnostics", checked this checked that for roughly 7 hours...got the car running damn near perfect, but it still won't take to full throttle. Here's what we did tonight:
oil was leaking out of the oil sensor, so we replaced that.
checked the distributor and plug wires (mine look near brand new, so we didn't think that's what was causing my issue, but checked it anyways).
checked again for leaks.
now here's the really funny part, when I would attempt to give the car full throttle before, it would bog down and you would smell gas (making me think that it's getting flooded). We changed the throttle position sensor (since I only drilled a hole in my old one and cleaned it, I didn't try a different one until tonight); put the new tps on, started the car, and it took full throttle twice in a row, then started doing the normal issue...bogging down if you punch the gas....we then realized that I had forgotten to plug in the tps, so I plugged it in, which fixed nothing, but we noticed that rather than smelling gas when the car bogged down, it smelled like exhaust.
At this point the car would just bog down but not shut of like it usually would when attempting full throttle..odd right?
I checked the power to my out of tank fuel pump, it was working fine..
Then checked the crank position sensor...my connector was cracked, so we took it off and replaced it off of the same '86 parts car described earlier...that didn't help much due to the fact that that crank sensor was in about the same condition as mine (with the exception of a "not as bad" cracked connector).
Took apart the old tps to see how the inside works, then adjusted my throttle cable with the new tps to where you can here the little sensor inside "click" when the throttle is at resting no throttle position.
After tonight the car starts fine, idles fine, drives fine, but you can't punch the throttle...you can ease into the throttle and the car is fine, but if you put the pedal to the floor quickly the car buckles down, yet doesn't shut off...
I'm thinking I still need to replace both of my crank senors (I know one is a crank sensor, not sure what the other is); after that I'm at a complete and utter loss as to what could be causing this issue. The motor sounds healthy as can be, no smoking, no odd ticking or clunking, etc. It's been maintained throughout it's life (I've got a folder full of service records dating back to 1987). Any and all insight will be appreciated! I'd really like to get this thing figured out!
Thanks in advance,
-Ted
. My main issue on the car is that it will not accept full throttle; it bogs down and backfires. I've been tinkering with the car for the past month, made some serious progress, but still not 100% right...bear with me everyone, this may get lengthy, but I'd really appreciate a thorough read and some thorough responses, if at all possible.
I obtained the car about a month and a half ago; was told that the fuel pump was bad. So I started there...that didn't fix my issue; I was having to start the car by fooling the ecu (put my thumb on the ICV and plugging in the hose leading to it from the intake boot right as the car would crank). Yes, I've checked for vac leaks, inspected all of my hoses and connections. Here's a list of everything I replaced and what it "solved":
valve cover gasket: did nothing
In tank fuel pump: fixed nothing :???: car still wouldn't start, the one time it did, it shut right back off
Fuel filter: ^^
(both of these parts above ^^ were from advance auto)
checked for spark and all 6 plugs were sparking normally
ICV: fixed sporadic idle after start up; car still didn't start on it's own (came off of a lower miles '87)
mass air flow meter: Again, idle was better, accepted slight throttle, but car still didn't start on it's own
cold start valve: car would start but then shut off, eventually the car wouldn't even start on it's own; car wouldn't accept full throttle
I suspected that the fuel pump wasn't putting out enough pressure, so I took back my advance auto pump and bought a used one out of a 1986 325es
(the icv, mafm, csv, oil sensor, and fuel pump all came off of the same parts, a 1986 325es)
At this point the car still wouldn't start on it's own..so I moved to the coolant sensors; I replaced every coolant sensor. The one that made the biggest difference was the coolant sensor with the two female connectors (not sure how to describe it, but it's the one on the very top of the thermostat housing with the two prongs sticking up...forgive me if that sounds ignorant :???:)
The car would then start on it's own, but would run for a little then bog down and have an oddly low idle, but could be driven and started after about 3 times turning the car over.
The next morning I went to start the car and it wouldn't start, I attempted to fool the ecu by doing my thumb trick on the icv..car still wouldn't start...eventually after about 20 minutes the car started but shook profusely! I shut it off and checked my SPARK PLUGS! They were completely, COMPLETELY gone...so I bought bosch replacements and the car started up and idled fine, but still wouldn't accept full throttle and would start on it's own consistently.
From there I checked my ecu; there was slight corrosion, so I replaced it with an ecu out of another 1987 325e. The car started on its own some-what easier, but was still finicky while driving and wouldn't take to full throttle. If you ease slightly into the throttle the car revs up fine, but if you punch the throttle, it would bog down and shut off.
Fuel pressure regulator: changed nothing
Fuel rail and injectors: tried a different fuel rail and injectors; car wouldn't even start, so I went back to my fuel rail, cleaned my injectors, and replaced a few o-rings, and the car started up slightly easier than before, but still wouldn't take full throttle
I then drilled a hole in my tps to allow oil to allow for oil to drain out and cleaned it with brake cleaner...that helped my idle slightly, but nothing else.
Here's a brief recap of everything I had done up until tonight so we (I) don't get lost in my own thoughts: icv, mafm, csv, drilled a hole in the tps, all coolant sensors, valve cover gasket, injectors, injector o-rings, fuel rail, fuel pressure regulator, fuel pump, fuel sender, fuel filter, spark plugs, checked for spark, and changed ecu.
Tonight I went to my buddy's shop tonight and we searched, did "diagnostics", checked this checked that for roughly 7 hours...got the car running damn near perfect, but it still won't take to full throttle. Here's what we did tonight:
oil was leaking out of the oil sensor, so we replaced that.
checked the distributor and plug wires (mine look near brand new, so we didn't think that's what was causing my issue, but checked it anyways).
checked again for leaks.
now here's the really funny part, when I would attempt to give the car full throttle before, it would bog down and you would smell gas (making me think that it's getting flooded). We changed the throttle position sensor (since I only drilled a hole in my old one and cleaned it, I didn't try a different one until tonight); put the new tps on, started the car, and it took full throttle twice in a row, then started doing the normal issue...bogging down if you punch the gas....we then realized that I had forgotten to plug in the tps, so I plugged it in, which fixed nothing, but we noticed that rather than smelling gas when the car bogged down, it smelled like exhaust.
At this point the car would just bog down but not shut of like it usually would when attempting full throttle..odd right?
I checked the power to my out of tank fuel pump, it was working fine..
Then checked the crank position sensor...my connector was cracked, so we took it off and replaced it off of the same '86 parts car described earlier...that didn't help much due to the fact that that crank sensor was in about the same condition as mine (with the exception of a "not as bad" cracked connector).
Took apart the old tps to see how the inside works, then adjusted my throttle cable with the new tps to where you can here the little sensor inside "click" when the throttle is at resting no throttle position.
After tonight the car starts fine, idles fine, drives fine, but you can't punch the throttle...you can ease into the throttle and the car is fine, but if you put the pedal to the floor quickly the car buckles down, yet doesn't shut off...
I'm thinking I still need to replace both of my crank senors (I know one is a crank sensor, not sure what the other is); after that I'm at a complete and utter loss as to what could be causing this issue. The motor sounds healthy as can be, no smoking, no odd ticking or clunking, etc. It's been maintained throughout it's life (I've got a folder full of service records dating back to 1987). Any and all insight will be appreciated! I'd really like to get this thing figured out!
Thanks in advance,
-Ted
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