Took my 1989 Firebird 305 TBI with 50k miles into Sears AutoCenter for a tuneup. They replaced plugs, wires, distributor, rotor, cap. Thereis now a constant, fairly loud ticking sound coming from the ignitioncoil-distributor area. The ticking rate is consistent with RPM, even at idle. Doesnot go away after driving a few miles. Stethoscope pinpointed sound to directlyunderneath the top of ignition coil (heard it myself). Replaced ignition coil,ticking still there but now it is not coming from under the new ignition coil.Also placed stethoscope on valve covers, headers, throttle body, and prettymuch everywhere else in the engine area and all sounds smooth. They can’tfigure out the cause of the ticking. Could it be possible they unplugged thetemp coolant sensor, pcv, egr valve, etc. during the tuneup, but didn’t re-seatthem properly? Could the new wires or plugs not be firing properly?
Car wasrunning fine before tuneup, although I’m glad I took it in because they showedme one of the plug wires was severely frayed. Any ideas? Thanks in advance! -Tony

 

One of the spark plug wires are coil wire is arcing .. check the boots at the cap, check for a wire arcing spark against the coil bracket.. or something of that nature.

if it the ticking speeds up with RPM that is clue it;s a problem with plug wire(s), high tension wire... etc.. try looking when it's dark... the arcing will be easier to see.

Better yet take it back to the shop who did the work and make them fix it... since they did the work in the first place.

 

Thanks for the information! It's been in their shop since yesterday afternoon and they still don't know. Would a solution be to replace each wire until it stops?

 

I want to toss in a vote for the new cap or rotor being defective , and the rotor is slightly contacting the cap and producing the tick .

I've seen it happen that one of the poles in the cap that the rotor is supposed to pass the spark off to had been cast crooked and was struck each time the rotor swung it's contact past it . In extreme cases it breaks the cap or rotor outright , and in lesser cases it barely hits and ticks ....

 

Thanks! I'll post the solution if/when they fix it.

 

if there is no visible arcing.. then I would suspect the rotor / cap.

either it was installed incorrectly (not seated onto the drive shaft)
the rotor tip is bent

or the dist. cap is not seated


Alot of these newer techs have never changed a distributor cap / rotor before since most of the vehicle on the streets today have coil packs...

if the work force at that shop is a bunch of young guys, and they can't figure it out (and you are stumped)find an older mechanic at a local garage

If that is the case that shop should reimburse you for the hassle..

 

They just called and said it's fixed -- they said cylinder 5 was misfiring. Another bizarre side effect of this tuneup is when I drove it yesterday the temp guage on the dash is stuck at 100, the lowest setting' and will not go up even after running for awhile. Even stone cold it doesn't sit all the way down at 100. Anyway, they said they didn't cause it. But it was working when I pulled in yesterday before the tuneup. He said the temp coolant sensor is seated and was never touched.
Any ideas on the temp guage?

 

BS

The sending unit is on the Driver's side of the block between #3 & #5 the passenger side has the radiator fan switch..

They probably knocked it loose or broke the connector when replacing the spark plugs & wires, after so many years the connector gets brittle and breaks easily.

have them check that before you take the car home...

Make sure they did not screw up the connector at the fan switch too...

 

Thanks so much for the replies. The problem was indeed a bad (or arcing or misconnected) spark plug wire causing the ticking. And the sender unit was disconnected as the cause of the temp guage issue just as you said. The shop had no idea about the sender, where it was, and where it reconnected. The car is running smooth as silk now.
Thanks again!

 

This is why the vast majority of the people on this forum do things like that themselves.

Take your Toyota Camry or Dodge minivan to a "shop"; learn to maintain your nearly antique "hot rod", such as it is, yourself.

 

Thanks for the advice, and I'm learning all I can. This is my fifth Firebird, but the first in about 10 years. This car is 24 years old, all original, and I just bought it a few weeks ago. The spark plugs are practically impossible to get to from the top, they looked rusted and I didn't want to take the chance of snapping one. I don't have a lift available, so I took it to a shop. This shop also replaced the shocks, struts, tires, and tie rods, and did an excellent job with that so I trusted them with a tuneup. I'm temporarily living in an apartment complex with no garage available. I'm stationed at an army base until September when I will get back home to my own garage.
I also took my Firebird to an audio "specialist" to install an amp, new speakers, and all new wiring since when I went to install new speakers the wiring was very brittle. Anyway, somehow they managed to burn out the power antenna which was working perfectly when I rolled in. So, yeah, I'm definitely learning that a lot of shops do not know how to work on older cars.
But I greatly appreciate this forum, where people can ask questions and folks are willing to help.

 

Yeah it's a real shame... but, that's pretty much how it's always been. "Mechanics" might be OK for something they see day in and day out, but something out of the ordinary, well, you takes your chances.

The plugs aren't really all that hard to get to. all except the rear 2 on the pass side come out easily from above; those other 2, are a piece o cake from underneath. Doesn't take a lift, a floor jack and a set of stands will do nicely. A little patience helps too, because there'll be ALOT of trial and error. (nearly as much error as trial) But it's not "hard", just, tedious.