My 88 mgm

[Elias]

Correction it does it at low speed too

[Elias]

I'd be more interested in the condition of the TFI module and the connector to it along with the PIP in the dizzy. Also the fuel pump and ECA relays. If you're not losing power when it dies and it just instantly dies... it's probably not fuel related (unless it's the pump). I'd also be checking the condition of the wiring to the fuel pump and making sure the ground line is secure. I don't remember where that is tied in though.

Sly Tfi was replaced about 6 months ago since when u helped me wire the relays I think. no not losing power all accesorios work car just dies it seams like it only does it at high speed thats why im think its fuel related since maybe it neew more fuel on highway idk

[sly]

I'd be more interested in the condition of the TFI module and the connector to it along with the PIP in the dizzy. Also the fuel pump and ECA relays. If you're not losing power when it dies and it just instantly dies... it's probably not fuel related (unless it's the pump). I'd also be checking the condition of the wiring to the fuel pump and making sure the ground line is secure. I don't remember where that is tied in though.

[Elias]

if you have steady vacuum on the EGR line, there is something wrong. Either the reg is jammed open or the plumbing is messed up. See if the foam filter on the regulator has disintegrated and clogged the little tube that sticks up into it. The filter lives under the cap on top of the regulator, which will pop off with a screwdriver. I've also had sticky regs that needed a honk of wd40 through them to clear the dirt out so they worked right before. If none of that fixes it, replace the EVR (egr vac regulator) or just leave the egr unhooked. You'll get a code for EGR not opening but that won't set a light.

So I cleaned the tb and IAC and its still dies it runs perfect fine it’s actually is running better than it has ever ran but when im on highway (most of my driving is highway) it dies. my cumute is about a 18 minute drive to work and it dies at least 2 time on the way over there I didn’t happened until about a few days ago. Spark plugs new msd cap new rotor new coil new battery new. Im wondering if something is wrong with the fuel up or fuel filter fuel pump is original and fuel filter i haven’t been replaced in a while.

[gadget73]

if you have steady vacuum on the EGR line, there is something wrong. Either the reg is jammed open or the plumbing is messed up. See if the foam filter on the regulator has disintegrated and clogged the little tube that sticks up into it. The filter lives under the cap on top of the regulator, which will pop off with a screwdriver. I've also had sticky regs that needed a honk of wd40 through them to clear the dirt out so they worked right before. If none of that fixes it, replace the EVR (egr vac regulator) or just leave the egr unhooked. You'll get a code for EGR not opening but that won't set a light.

[Elias]

Ill check the egr tomorrow it probably is that. Because when i connect the egr vacuum the green hose line it starts shaking alot. So I disconnected the hose and it works better.

[gadget73]

Smog pump won't trip the CEL. Possible the EGR code is doing it though. Not many things actually trip that. The two times I had it happen on my Mark VII, once was an EGR problem, the other was a bad TPS. Smog pump is gone on that, no CEL.

[Elias]

If the smog pump is gone, 44 and 94 will not go away. If the pump is there, fair chance the passages in the back of the head are clogged, or the vacuum stuff that actually turns the pump on and off are not working. If all of it actually works and the passages are not clogged, it means the O2 sensors aren't working properly.



Code 34 you can poke a voltmeter into the EGR position sensor to see whats going on. Read from EVP to SIGRTN, not sure what the colors are without digging up a manual

http://www.grandmarq.net/oldfuelinjection/page35.html

If the valve is definitely closed, see what the voltage output is. File the end of the EVP if its slightly off. If its way off, replace the position sensor and check again.

an egr valve hanging open will cause you idle problems, so might be worth pulling that off for a check while you're in there.

I Did delete the smog but would they couse the cel to come on too. Thats the main thing that is bothering me. I want that cel off with out removing the bulb for it

[gadget73]

If the smog pump is gone, 44 and 94 will not go away. If the pump is there, fair chance the passages in the back of the head are clogged, or the vacuum stuff that actually turns the pump on and off are not working. If all of it actually works and the passages are not clogged, it means the O2 sensors aren't working properly.



Code 34 you can poke a voltmeter into the EGR position sensor to see whats going on. Read from EVP to SIGRTN, not sure what the colors are without digging up a manual

http://www.grandmarq.net/oldfuelinjection/page35.html

If the valve is definitely closed, see what the voltage output is. File the end of the EVP if its slightly off. If its way off, replace the position sensor and check again.

an egr valve hanging open will cause you idle problems, so might be worth pulling that off for a check while you're in there.

[Elias]

Have you cleaned the throttle body with throttle body cleaner?

This will not fix the remaining codes.

No I haven’t cleaned it yet i did clean out the egr. I will be doing the tb and iac after work.

[jaywish]

Have you cleaned the throttle body with throttle body cleaner?

This will not fix the remaining codes.

[Elias]

Checked for codes again and now im only getting
94
44
34
But car been stalling sometimes for no reason still.

[Elias]

I bought a new one and now it’s reading at 0.98 cel is still on but it does seem to ideal better

[Elias]

Okay so I measured it and its ready between 0.61 and 0.62 im guessing the tps sensore is bad

[gadget73]

Its not really adjustable, but you can modify it. First thing to do is figure out if the throttle body screw is turned in too far. Unplug the idle control motor and see what it idles at. It should be around 500 rpm. If its above that, back the screw out until it idles down.

Once the throttle is known to be in the right area, poke a voltmeter into the TPS connector from black to green. The OK range is something like 0.8 to 1.2, but usually aiming for as close to 1.0v as practical is advised. If yours is just totally wrong and the TPS is good, you can file out the two holes where the screws pass through to turn them into slots that will allow it to rotate. Make sure the two little ears in the TPS that engage the flat part on top of the throttle shaft are not broken. You'll usually see low voltage and it won't increase when the throttle is opened if those are broken. When you put the TPS on, you'll usually need to install it with the mount ears in-line with the intake and rotate it to line the screws up. You should feel when the TPS contacts the ears by the bit of extra resistance rotating it.

Mustang shops should know this. Its all the same stuff on the Fox cars.