Rescuing my dads old Fiero GT 1987 (Page 19/23)
Repulsiv JUL 26, 06:50 PM
I fixed both the battery connections and grounding, and its so strange that it works perfectly most of the times, and then one time just.. NO..

I placed an order on rockauto today, on a LOT of things.. gaskets for the calipers, all brakepads, oil/air/fuel filters, PCV, thermostat, dist cap, rotor, ignition cables, sparkplugs, pickupcoil ignition module.. bulbs, lampholders, generator belt.. and more..

I really hope that I elliminated most problems after that
Rexgirl JUL 27, 05:01 AM
Your starting problem may be in the ignition switch. It is adjustable and if it has moved out of proper position, the 'start' contacts might not always be making contact in an older switch. Or, on manual transmission cars, there is a switch on the clutch pedal that is also part of the start circuit. Finally, there is a linkage in tilt steering columns that can bend.
Rexgirl JUL 27, 04:28 PM
The ignition switch is mounted on the steering column near your left knee. Here is a pic (thanks Jetman, I think?) of the blue ignition switch with the headlight dimmer below it:


Most likely, it will need to be moved toward the steering wheel
Repulsiv AUG 05, 08:34 AM

Hmm, interesting about the switch on the steering collumn, I will look at that!

anyway..

Friday i recived my things from rockauto.. I thought.. in reality I got 2 out of 3 boxes.. fedex simply dont know why the last one is "on a truck somwhere" gah..

Unfortunatly most of the ignition parts where in that last box, but I swapped the ignition cables (the only ignition-part in the boxes I recived), didnt help at all - just like expected.

A bad thing also was that the cables I had in the car they where different lenghts, the belden-cables I ordered had just two lenghts so it didnt look that nice.

I also swapped the airfilter and thermostat, and some bulbs and other small stuff.

Since my fam is away a week I could also take a few testdrives (usally the fiero is located behind another car) and noticed something, the misfires only occures while reving
or accelerating (same thing basically..), if I driving in one specific speed and maintain that there is no misfires at all.

That lead me to thinking if there is a problem with the ignition timing-advance ? ..how is it done on those engines ? is it mechanical in the distributor, or fully electronic ?

..Anyway, fedex say I MIGHT get the missing box on monday, then I get new stuff to try with..


..I also tryed to remove the cable on the temp sensor again.. how the h**l.. its so tight, I cannot neither fingers or pliers down there ??


when I swapped the airfilter I also found that one of the vaccumhoses on the cruise control was broken, so I cutted a part of it so it shouldent leak anymore, but no difference.
tshark AUG 05, 09:11 AM
I beloeve the timing is manual with the distributor.

You could check the MAP sensor and the TPS, but vacuum leaks are often the issue. Vacuum leaks from the cruise cannister, around the EGR, etc. You could have a blockage going to the MAP sensor.

Oh. Which temp sensor? By the thermostat housing, or by the distributor? I'm guessing by the thermostat housing.

[This message has been edited by tshark (edited 08-05-2018).]

Patrick AUG 05, 11:48 AM

The ECU advances the ignition timing.
Repulsiv AUG 07, 01:30 PM
Hmm.. today the box arrived finally.

I started with swapping rotor and distributor cap, HOWEVER, the new one had screws with inch threads, and the old one had millimeter.. so ofcourse I broke one screw..

To remove it I had to remove the distributor so I did.. and when it was loose anyway I disassembled it and swapped both the pickupcoil and the ignition module, removed the broken screw and
used the old screws, replaced rotor/cap and removed ignition lead to be SURE I had oil pressure, I GUESS the axel down on the distributor actually drive the oilpump as it does on many other engines..

Anyway I had oilpressure so back with the ignition cable and tried to start, first it didnt start and when I double checked the firing order I noticed I swapped two cables by mistake, oops, put those back in the correct way and now it started.

I took a testdrive and.. NO.. misfire exactly as before.

Now the only thing I didnt swap was the sparkplugs, and I have new one so I will.. I really hope it wasnt the sparkplugs all the time, then i put a lot of energy, time and money in the wrong places..

..On the other hand, the pickupcoil REALLY needed to be changed anyway, it went in pieces when I removed it, the copper was green and the plastics where like cooked pasta.. its hard to belive it actually worked, and since the ignition module is a known problem area it can be nice to have a extra spare.

Well, if its not the sparkplugs, any other ideas ?

[This message has been edited by Repulsiv (edited 08-07-2018).]

Repulsiv AUG 07, 01:39 PM

quote
Originally posted by tshark:

I beloeve the timing is manual with the distributor.



Now after disassebled it, it sure didnt have any parts for it inside..


quote

You could check the MAP sensor and the TPS, but vacuum leaks are often the issue. Vacuum leaks from the cruise cannister, around the EGR, etc. You could have a blockage going to the MAP sensor.



I try to find them and see, but i think i already cleaned the connector to the TPS, but I havent seen the MAP sensor.

I been hunting leaks with startgas and my eyes, but havent found any, except the hose on the vaccum canister.


quote

Oh. Which temp sensor? By the thermostat housing, or by the distributor? I'm guessing by the thermostat housing.




The one for the radiator fan,. someone posted a "map" over the tempsensors before I think, I printed that one

[This message has been edited by Repulsiv (edited 08-07-2018).]

Rexgirl AUG 07, 03:54 PM
If changing the sparkplugs does not quicken the starting time, check your fuel pressure, both while running and during the 10-20 minutes after you shut the engine off. There is a valve the tester can connect to just below the large vacuum tap (10mm?) on the right side of the intake manifold (to the right of the "O" in the 'Fiero' casting). The black rectangular plastic MAP sensor is immediately rearward of that tap, btw.

Your intermittent starter motor problem is very likely in the starter itself. but I suggested the ignition switch as there is a small possibility of a current drop there or at the clutch pedal interrupt switch.
Repulsiv AUG 18, 05:42 AM

Yesterday I was going to replace the fuel filter, just because a clogged filter can make the engine hard to start, and make it go bad under acceleration, and also I bought a couple of fuel filters, it probably need a change anyway.

However, the first point was to remove the fuse for the fuel pump, and I noticed that the fuse was heavuily corroded, so I cleaned that one, and looked at the other fuses, they where all corroded, so instead of changing the fuel filter I ended up cleaning the fusebox..

After I done that I tried to start the engine just to see if that was the problem, and it started instantly! ..let it idle a while, stopped and tried to start again, no.. now I had to crank it for like 10s before it started, I stopped again and the same again.. 8-15s or so every time.

But, now this that I noted earlier (when it was a lot more troubles):


quote
Originally posted by Repulsiv:
I also nothed something else, sometimes when I try to start the rpm-gauge does not move at all, and it it suddenly ignites I can see that it jump up.

Does the meter and the ignintion control take the rpm signal from the same place ? ..then I could be onto something here..



Now its extremtly clear that this is related to the starting problem, because when the engine does not start the rpm needle is at zero, as soon as it jumps up (while cranking) the engine start to ignite and start.

So it seem like the engine do not get any signal and therefore doesnt ignite, as soon as it work it starts, this seem to be the root of the start-problems, not sure if its the same problem causing it to misfire under load.

I wish I had a logical or electrical schematic of just the ignition system, i have a feeling I have oxide somewhere.. maybe between the ECM and the distributor ?