1988 2.5L Distributor Cap and Rotor (Page 1/1)
enicho1 FEB 09, 05:34 PM
I just bought a 1988 Fiero 2.5L and needing to install new brakes, and a tune up, etc.

I can’t find anything for a Distributor Cap and Rotor as the auto parts stores, and even Rockauto don’t list a cap & rotor.

The GM parts direct pages also list the cap & rotor as discontinued.

I looked at 84 thru 86 and there are listings for the 4cyl 2.5L, but 87 and 88 don’t show anything for a distributor cap and rotor for the 4cyl.

Anyone know what can be cross used as a parts reference, like a Chevy S-10 with the 2.5L?

This is strange that no cap and rotor are listed anymore.

Thanks for any help or light you can shed.
skywurz FEB 09, 05:41 PM
It does not have one. The distributor is a mag pickup no rotor.
zardoz FEB 09, 05:46 PM
I believe the '87 and '88 2.5L engine systems did not use a traditional rotating distributor. The used a coil pack and solid state ignition module that was controlled by the vehicle computer. It was known as a "wasted spark" ignition system. The coil pack fired two plugs at the same time in alternating sequence with the other two plugs. One spark was at top of compression stroke (where it ignited mixture, and was "not wasted"), and the other was at the exhaust stroke. The "wasted" spark occurred in the cylinder on the exhaust stroke that had no compressed mixture to ignite.

[This message has been edited by zardoz (edited 02-09-2022).]

enicho1 FEB 09, 05:58 PM
Oh wow.
Man I feel dumb.

I had an 84 way back 30 years ago.
I used to know a lot about working on it.

I figured a 1988 would be great, then it was uh oh…
Looking at what I though was the distributor down low on the engine, never even crossed my mind it could be a coil pack.

Well, I really appreciate the help.

Thank you very much
Patrick FEB 09, 06:03 PM

quote
Originally posted by enicho1:

This is strange that no cap and rotor are listed anymore.



It's not strange at all.
theogre FEB 09, 10:55 PM
87-88 is another engine and doesn't have those parts...

See my Cave, Duke Quick Ref, DIS Ignition and 700 TBI

"tune up" in your case is replace spark plugs and old wires.

anytime you pull spark plugs keep them in order.
If #4 is cleaner than other 3 very likely have coolant leak in intake casket. if bad enough that can cause ignition missing etc. sim to bad plug(s) and other ignition parts.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

enicho1 FEB 10, 01:18 PM
Thank you for that heads up on keeping the plugs in order.
This might be what is happening because it is missing, and hard to start.
It cranks way longer than it should.

I also have an 86 GT 2.8L and that starts right up, but runs a little rough and misses too.
But that definitely has a distributor cap and rotor.

Many thanks for the help and sharing.
Really appreciate it!
olejoedad FEB 10, 02:05 PM
Cranking a long time could indicate that the fuel pump relay is inoperative, and the fuel pump in being energized by the switch in the oil pressure sending unit.
enicho1 FEB 10, 02:23 PM
Thank you also for the hint on the fuel relay.
Man, I never would have thought the relay…. At all.

Very very much appreciate the knowledge!

Can’t thank everyone enough !!!

Thank you 🙏
theogre FEB 10, 05:46 PM
Duke DIS engines often crank longer. More so w/ cold start.
Try turn key to start for a few sec. If engine doesn't start, stop hold key to start but do not turn key off either, wait 1-2 sec, try again.
This often starts faster then 1 lonnnggg cranking.

Even using Wells DIS Modules that makers claim "starts faster" then OE doesn't help much here.

Do Not use "gimmick" plugs. Read DIS page again before buying.
Basic plugs or Champion and Autolite Double Platinum are good w/ this coil on any engine.

As to F-pump running or not...
Turn Key On.
Should hear F-pump running then stop in a few sec.
⚠️ Some F-pumps are quieter then others even w/ OE ones. Pump and actual installing them and fuel level can affect noise level.
If still can't hear for outside noise etc, put test light between ALDL G and frame. Light should be On as Turn Key On same as before.
If you then turn key to start, pump/light should turn on again and stay On when engine runs.
See my Cave, ALDL/ALCL