No start, please help!

[M3PO]

'84 325e, previous owner says he swapped in a seta (not sure here). Driven short distances a few times a week.

The weather has been damp/drizzly lately and the car had a few "hiccups" where it would lurch under heavy throttle at low RPMs. This may or may not be water/humidity related. The car has not been driven (recently) while it was raining.

Last friday is when the real problems started. It started and ran fine for 3-5 mins. At a light, the temp gauge was going nuts, it started idling very rough, and died. Started up fine, died a block later. After a few more iterations of this, starting harder every time, finally it wouldn't start.

An hour later, it started fine but idled rough. Eight hours later, it started and idled perfect. After a few minutes of driving, it started to idle very rough but I shut it off before it could die.

Tonight, it wouldn't start at all. The car has fuel, I can smell it at the muffler, and there is liquid fuel pooled in the intake boot. A couple of times it turned over a couple rotations after I let off the key so it seems like it has some spark. I can hear the injectors clicking and the fuel pump running during cranking. The coil looks fine (no cracks). No significant vacuum leaks. Nothing obvious.

What are the prime candidates? Bad DME? CPS (don't know where it is)? ICV? AFM? Distributor? Thanks!

[dnguyen1963]

Leaky injectors or you have the wrong injectors with stock chip.

[M3PO]

The engine is all stock. It ran perfectly with this chip an injectors for the last 18 months that I have owned it.

Wouldn't it still run with a leaky injector?

[M3PO]

About a year ago, it failed smog and at that time, the shop said it had a "lazy" O2 sensor. If it were the O2 sensor, it would still run when cold right? And would run with it unplugged?

[M3PO]

Checked the coil, I have strong spark at the coil. Spark at the plug wires.

I've got fuel.

I can hear two of the relays on the driver's fender click.

The ICV doesn't make any noise at all but the car doesn't start when I push the throttle pedal during cranking so I don't think it's that.

It would run without the temp sensor right?

Would it start with a bad AFM? I'm running out of ideas...

[truekid]

Could be a faulty CPS there are two on e's. Both located on the bell housing of the transmission closer to the slave cylinder.

You can pull off the distributor and check the contact points?

Have you check the plugs themselves? (Probably not them but simple enough to rule them out)

Check the ground around the motor? maybe a lose connection?

Just throwing out ideas.

[M3PO]

Thanks, any ideas are appreciated! If the CPS was bad, the DME wouldn't start the FP and fire the coil right? Since I have spark at the plugs, doesn't that indicate that the distributor is fine? The plugs don't look great but I get a strong spark from them.

I will check the ground.

I tried to start it with the brown, single pole temp sensor disconnected. No difference. Same thing with the O2 sensor, no difference.

[M3PO]

No difference with the AFM unplugged. It wouldn't start with starting fluid squirting it into the intake boot with the AFM totally off.

[M3PO]

My two prong ICV has 10 ohm resistance and clicks open and closed when 12V is applied. When the ignition is on, the ICV is getting 9.8V when the battery has 11.5V (dead), not sure what that means. It seems like the ICV is fine but it doesn't make any noise when the ignition is on.

TPS is working properly, 0.00 ohms closed and infinite resistance when open, back to 0.00 ohms at WOT.

Both crank sensors (it's an eta) show 970 ohms.

The AFM has roughly the correct resistance when closed but doesn't increase linearly like it should. I don't think that this would stop it from running.

[M3PO]

Also, I pulled the distributor cap off. It was clean inside, no cracks. Just some buildup (carbon?) on the points. I dunno enough about distributors to know if this is bad but it seems fine. Rotor seems fine too.





Also, these plugs are toast right?

[M3PO]

Okay, so I sanded the points and rotor as clean as possible when I put the cap back on the distributor. I didn't change anything else other than reassembling things after I was done checking them. I put it on a battery charger because it was dead from trying to start it so much.

AND it started easily, first time. And it restarts fine. The only issue that it seems to have now is that it will bog if you give it gas too quickly (like if you rev it). You can actually kill it. If you push the gas slowly, it's fine. The strange thing is that it stopped doing it after I drove it for a few minutes.

[jlevie]

Check the rail fuel pressure when driving. And ditch those plugs and install a set of NGK ZGR5A plugs.

[dnguyen1963]

The strange thing is that it stopped doing it after I drove it for a few minutes.

The ECU needs time to adapt to the new environment. And yes, replace your plugs.

[M3PO]

Thanks guys! I just ordered the Bosch "silver" plugs that Pelican recommends as a replacement for the OE plugs.

Also, I think that my issue may be related to the temperature switch because I also have a slightly high idle and it smells. The contacts are loose and pressing on them causes the idle to drop to the normal warm idle point.