Seeking opinions 89 Grand Am 2.5L

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This car which remained with title et al. when my ex left has been sitting in my driveway a few months. It used to run well enough but in the cold weather you needed to put it in drive and wait a while before it would actually move. Then it decided to not even start.

Here's my question:
Shall I call the local car breaker's yard to come take it away or is there something similar to my EEC IV on my T-Bird where I cold relatively simply look at engine codes to see why it won't fire up and thus possibly get it running, even as a back up car or even a starter car for my Daughter when she gets her licnese in a few months.

If it stays on the property it should be made to run - currenly I'm more inclined to dump it as a google search gave me no indications of codes or modules in the same way the T-Bird search did. Maybe I'm asking the search question wrong :laughing:

posted by  HighWayMan

I say keep it. Although i'd say that about any car in a junk yard. I see the potential for a beautiful machine in every car I see.

How about we get started on the diagnosis! :thumbs:

Does it turn over?
IF SO
----------
Getting spark? Strong spark?
Getting fuel? Good pressure?
Check if you have water in your gas.
IF NOT
-----------
Battery voltage - no load =?
Battery voltage - headlights on =?
Starter relay closing?



OTHER INFO
---------------
Since it's been sitting awhile, I will give you a few recommendations for long storage start-up by me :laughing:
First of all, dump the oil thats in it now. And filter. New filter, new oil. Check all fluids, check belt tensions, check battery voltage.


P.S: As for your question I have no clue what your really asking, but if your asking if you can check trouble codes with the key on an engine off them I'm not sure on that car.

posted by  DodgeRida67

Useful site thanks Maybe I'll get something done on it this weekend but as background the car has sat without a battery for the winter. Before that the motor turned healthily but no spark. Someone replaced the sensor for the ignition module when it was left in my driveway and they actually gave me the old sensor they took out as it didn't correct the problem. if it had they would not have left the car there :). I believe fuel is flowing I can certainly smell it whe the starter is spun (span? spinned?).

Another adventure in this car :)

posted by  HighWayMan

No spark means one of several things - coil pack, ignition module, crankshaft sensor, camshaft sensor, etc.

When you get the troubls codes, we can see if it leads to anything directly or if we need to get the digital voltmeter and test light and start hunting

posted by  tbaxleyjr

have you tried clening the plugs then bump startin it? if its been sat then they probibly got gunked up.

posted by  cinqyg

Post after post have I seen you spell that one word wrong. It's "probably" not "probibly". :thumbs:

posted by  DodgeRida67

Good isnt it. I dont care in all honesty. You lot spell gauge guage. Everyone understands what i mean. Surely thats the point.

posted by  cinqyg

When I spell gauge "guage" it is a simple typo because I know how to spell it correctly. However when someone spells something wrong not knowingly, it's a good person that tells them they're spelling it wrong. It's like telling someone their shirt is on backwards or they have food in their teeth. It's not ment to be taken offence for, it's a nice thing really.

posted by  DodgeRida67

i have thing thing were i type becuase instead of because, its one of those sub concious things, my fingers do. thanks for pointing it out, but im not likely to change it, im not that great with spelling, i will stick to 5 dimensional mathmatical modeling, i know how to do that.

posted by  cinqyg

I am proud of you if you can do 5 dimensional "mathmatical" modeling. The books you had at the university spelled it mathematical modeling

posted by  tbaxleyjr

getting back to the topic,

adding to the ignition system issues I mentioned earlier, cinqyg, suggests inspecting and cleaning the plugs. If going to the trouble of pulling them, the ones on the GM 2.5L L-4, Autolite 664's or 666's ara only about $1.00 ea @ Wally World. The gap is 0.060

Once the car is restarted, It could probably benefit from fresh fuel and a strong dose of fuel injector and carb cleaner

posted by  tbaxleyjr

I didn't get time to look at it yet but the plugs and leads are new. As is the crankshaft sensor. Agreed on replacing the fuel and the injector and carb cleaner but no point going there until I find where the spark went. I did verify no spark on any plug.

posted by  HighWayMan

Did you have to replace the entire DIS assembly/coil pack with the crank sensor or did it come separately.

I'll try to find a wiring diagram between now and the weekend

posted by  tbaxleyjr

I actually didn't do it but just the sensor was replaced.

posted by  HighWayMan

I actually didn't do it but just the sensor was replaced.

I checked the old one with a magnet and Ohm meter it sensed and gave a kick but that's hardly proving it perfect.

posted by  HighWayMan

Let us know when you get a chance to pull the codes.

The crankshaft position sensor voltage pulses should be on the order of magnitude of 5 volts.

Areas I would be concerned since we are dealing with a no spark

If the no spark is for all four plugs, the first thing I would look for is a bad ground @ the ignition module/DIS unit or a bad ignition module. The only sure way someone @ home can test is to replace with a good one
The crankcase position sensor is should be OK if new.

I posted a follow up describing how this system works

posted by  tbaxleyjr

I have a couple of minutes to digress on the ignition module on a GM DIS system

According to a schematic I found

The ignition module (under the coil packs) acts as the interface point between the crankshaft sensor, the ECM, and the ignition coils. This module sends the approx 5 volt pulse tach signal to the ECM

One should be able to backprobe the ignition module connector and get voltage readings on the 6 wire connector

Upon cranking start up, the ignition module controls the ignition timing and a 5V signal is sent to the ECM (circuit 423 - white wire). When the engine speed, determined from the tach signal by the ECM approaches 400 rpm ( circuit 430, the purple wire w/ white stripe is the engine speed signal), the the ECM sends a 5V bypass signal (circuit 424, tan w/ black stripe) to the ignition module bypassing the timing control loop in the module with the ECM assuming control of the ignition timing functions based on its other inputs. The black wire w/ red stripe is the signal ground back through the ECM (circuit 453) The white wire (circuit 121) is the tach signal to the instrument panel or other tach connection

There is also a 2 wire connector which should measure battery voltage between the terminals on the harness side with ignition switch on. The black wire w/ white stripe leads to the engine ground

Hope this helps

posted by  tbaxleyjr

Thus since I don't get past cranking startup I should be able to look for that 5V signal on the white wire to see if the ignition module is doing its job?

Thanks.

posted by  HighWayMan

I would backprobe and see if If I am getting voltage signals (5V on circuit 423 (white wire) or signal on the pruple w/ white stripe wire)
http://www1.autozone.com/servlet/UiBroker?ForwardPage=az/cds/en_us/0900823d /80/0e/4d/bc/0900823d800e4dbc.jsp
http://www1.autozone.com/servlet/UiBroker?ForwardPage=az/cds/en_us/0900823d /80/09/d4/90/0900823d8009d490.jsp
I was looking for something else and found these diagrams which will help One is a connection diagram identifying the terminals and circuits for the GM L4 ignition module, the other is links to the engine control wiring diagram

http://www1.autozone.com/servlet/UiBroker?ForwardPage=az/cds/en_us/0900823d /80/0e/4d/ad/0900823d800e4dad.jsp
is a good general description which correlates with what I mentioned earlier

posted by  tbaxleyjr

OK I had to borrow a battery from another car but the codes this is giving is just to repear contunuously code 12. After about 1/2 hour I decided it wasn't going to stop or do anything else.

posted by  HighWayMan

Code 12 on a GM means the car is in diagnostic mode. No codes narrows things down to the no battery voltage @ ignition module,located under the coil packs (check wiring and fuses), a bad ignition module, maybe a bad crankshaft position sensor or by a remote possibility a bad ECM Did you backprobe the ignition module terminals identified in an earlier post while you had the good battery?

posted by  tbaxleyjr

Nope I have to get a high impedance voltmeter, I only have an olde moving coil instrument.

posted by  HighWayMan

that would be a good move - an analog meter will fry the electronics

posted by  tbaxleyjr

I'm not going to get back to this for a couple of weeks. So I'll post again when I do get to it.

posted by  HighWayMan

I'm not going to get back to this for a couple of weeks. So I'll post again when I do get to it.

posted by  HighWayMan

Well I finally got back to this with a digital voltmeter only to find the module is at the rear between the engine and firewall under the manifold How to test here when you can't even see the wires has me puzzled unless I can locate the other ends of the wires. Even then replacing the module if that's the culprit looks a real challenge with big hands like mine which have trouble fitting there. Increasingly this is looking like a dump the car job!.

posted by  HighWayMan

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