Drove with loose distrubutor...heeelllp!

[webshot]

My brother had the timing set by some numb nut who didnt tighten the distrubutor all the way down. Well he drove the car quite a ways and it barely made it to my house, limping. I re-timed his car, set it to 12 (he uses 91 octane gas), and tightened his distributor. Now it seems all is well, BUT...now the car wont hold idle and drives real rough (almost feels like it is out of gas). When he did drive up and shut the car off a nice plume of smoke came from the back area by the egr valve. At this point we want to take the car to a professional, but I want to ask the pros here, if there are some simple/pre shop things I can try at home, or what are some possible outcomes or damage done to the engine. Or for that matter any advice or experience with anything like this.

Any input greatly appreciated.

Car starts up just fine. ANd just a bit of more info that may help. Car had some hot start problems which was said to be linked to the timing. If that was true or not I dont know, but that is what lead the cars timing to be looked at in the first place. Figure that may help.

 

[cjones]

check the PCV valve and lines and all the vacuum hoses. if it backfired bad one may have blown off.

any codes??

 

[webshot]

I will check those. It did backfire quite a few times. No check engine light. Should I check codes anyway?

 

[cjones]

I will check those. It did backfire quite a few times. No check engine light. Should I check codes anyway?

yes, just because the light is not on doesn't mean there aren't codes.

 

[HISSIN50]

Did you clear the KAM after resetting the timing? I have to wonder if all the trims were out of whack after it tried to deal with wandering timing (affecting IAC DC, load calc and so on, right down the line).

I'd get them codes like everyone suggested, and clear the KAM.

Good luck.

 

[webshot]

I would say no to the KAM, since I dont really know what that is. What is the KAM?

Thanks for the advice guys. PLease feel free to pass more info along. I will check codes today (looking for the famous Jrichker post on checking codes).

 

[ARTTII]

KAM = keep alive memory

 

[ninety15.0]

You can clear the KAM codes by stopping the code reader or pulling the jumper wire while the car is in the process of kicking out the codes. This will stop the test and clear the KAM. I would agree with Hissin...trims are probably all messed up from dealing with strange/changing timing. Check Jrichker's surging idle checklist for the proper code pulling procedure with a paperclip! I use it all the time!

 

[webshot]

Thanks guys, will try everything suggested. The good thing is so far I have heard "aaawww man that car is toast you need a new engine". Can anyone tell me what the worse case scenario is with driving with a loose distributor? It wasnt to loose to the point where it would come out, but you could twist it with a little force.

 

[mike88gt]

Make sure the spout connector has been replaced. The car needs to be timed with the spout connector removed and then replaced when finished. Here is a link with instructions. http://www.muscularmustangs.com/timing.php .

As suggested, check all the vacuum lines, pvc and egr valves. Some are hard to see, especially up under the upper intake manifold. If it backfired, a line could be split or blown off. Pull the sparkplugs and make sure they aren't fouled and check that all the wires are connected correctly and routed to the correct cylinders. Find a wiring diagram for your 5.0 and use it. There could be multiple issues if someone else was fooling with it. Before starting all that, disconnect the negative battery terminal and leave it until you are finished, this will reset the computer to default and clear the codes.

Good luck

 

[webshot]

Ok ran my codes and I came up with a code 34. It flashed 3x's pause then 4x's. It did this 2x's then stopped. Am I interpreting that right? Also given the above issues could it be the egr valve is no bad?

Any advice appreciated.

 

[webshot]

Found this info by Jrichker. I have a volt meter but dont know all the acronyms to test the right stuff for resistance.

Code 34 Or 334 - EGR voltage above closed limit - Failed sensor, carbon between EGR pintle valve and seat holding the valve off its seat. Remove the EGR valve and clean it with carbon remover. Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. If it leaks, there is carbon stuck on the pintle valve seat, replace the EGR valve ($85-$95).

If the blow by test passes, and you have replaced the sensor, then you have electrical ground problems. Check the resistance between the black/white wire on the MAP/BARO sensor and then the black/white wire on the EGR and the same wire on the TPS. It should be less than 1 ohm. Next check the resistance between the black/white wire and the negative battery post. It should be less than 1 ohm.

Note that all resistance tests must be done with power off. Measuring resistance with a circuit powered on will give false readings and possibly damage the meter.

Let’s put on our Inspector Gadget propeller head beanies and think about how this works:
The EGR sensor is a variable resistor with ground on one leg and Vref (5 volts) on the other. Its’ resistance ranges from 4000 to 5500 Ohms measured between Vref & ground, depending on the sensor. The center connection of the variable resistor is the slider that moves in response to the amount of vacuum applied. The slider has some minimum value of resistance greater than 100 ohms so that the computer always sees a voltage present at its’ input. If the value was 0 ohms, there would be no voltage output. Then the computer would not be able to distinguish between a properly functioning sensor and one that had a broken wire or bad connection. The EGR I have in hand reads 700 Ohms between the slider (EPV) and ground (SIG RTN) at rest with no vacuum applied. The EGR valve or sensor may cause the voltage to be above closed limits due to the manufacturing tolerances that cause the EGR sensor to rest at a higher position than it should.

This will affect idle quality by diluting the intake air charge

 

[cjones]

which acronyms are you not sure about??

 

[webshot]

Check the resistance between the black/white wire on the MAP/BARO sensor

slider (EPV) and ground (SIG RTN) at rest with no vacuum applied.

Those are basically the parts I dont understand

 

[jrichker]

BUZZZ...WORDDSSSS...

MAP/BARO sensor Barometric pressure sensor - it lives on the firewall behind the
upper intake manifold on 86-93 cars. On 94- and later cars, it is inside the computer.

The black/white wire is the signal ground for the EGR sensor and several of the other
sensors. It goes from the sensors to the computer and then to the computer power
ground by the battery chassis ground. Sometimes the black/white signal ground wire
develops a bad connection or broken wire. That messes up the sensor's output voltage
and triggers the code 34.

The first two paragraphs contain all the troubleshooting detail. The remaing paragraphs
are explaination of the theory of operation. As for the rest of the verbage in your case,
it isn't too important. The values will very from engine to engine and the primary idea is
that it isn't 0 ohms or 5000 ohms.


Diagram courtesy of Tmoss & Stang&2birds

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

 

[88blacklx]

i highly doubt you hurt the engine that way. Are you sure the timing is set correctly now? becuase if its still backfiring it sounds like you still may be off

 

[mike88gt]

The codes don't mean much if you have a major malfunction and a bunch of unknowns. Did you check the vacuum lines as another founding member suggested and follow along with my instructions? You need to do a base timing adjustment with the spout removed, check the basics, clear the codes and run it again to see what happens. Too many things might have happened and you need to do some troubleshooting in a logical order to nail down the problem. You gotta find out what it's not to find out what it is.

A bad EGR can make the car run like crap and will kick codes, but you gotta do the basics and a reset to find it.

jrichker - nice diagrams - good job!

Finally got my smog pipes out and can hear the cam, been years since I drove the beast - taking the 88 out this weekend.

 

[webshot]

THings I have done thus far.

DId the base code timing as suggested.

Checked vacuum lines.....one did bust but I fixed it.

Took off egr valave cleaned it with carbon cleaner, replaced it rans codes again.

Oh and I dumped KAM as suggested earlier. Only thing I have yet to do is check the voltage as jrichker suggested. I am still re-reading to make sure I know what the hell I am doing. The diagram may help.

The egr valve was very very very crusty and cleaning it didnt help very much (as far as getting crust off).

But so far after all this the car is running like crap still and wont hold idle. Starts up perfectly but it is all downhill after that.

Oh and I changed my wires, one was arcing. Gonna change plugs today too.

 

[jrichker]

This comes to mind in reference to the EGR valve...

"Prior to re-installing see if you can blow air through the flange side of the EGR by mouth. If it leaks, there is carbon stuck on the pintle valve seat, replace the EGR valve ($85-$95)."

 

[webshot]

New egr, and get a code 11, which is system ok.....Car still runs like crap tho