engine issues after reinstallation

Chris71383 · 06-05-2013, 09:34 PM

Ok, pulled the engine from my wrecked 88' 924s and did a full reseal, new rod bearings, new clutch, new water pump, belts, most of the rollers, and a refreshed head. Installed it in my 87' 944, pulled the fuel pump fuse and primed the engine before I tried to start it and everthing sounded great. Put the fuse back in and it sounds like it wants to start kinda stumbles then I get a high pitch whistle/pop from the engine. Any idea, timing issue maby?

John_AZ · 06-06-2013, 03:21 AM

Are you using the DME from the '88 924S?

J_AZ

Chris71383 · 06-06-2013, 03:32 AM

yes

John_AZ · 06-06-2013, 03:49 AM

Have you double checked the plug wires from the cap?
http://www.clarks-garage.com/graphics/distcap1.gif

Did you reverse the reference sensor wires?
Speed and Reference Sensors - Checking, Replacement, and Adjustment

You probably have double-triple checked the timing marks---is the rotor on tight?

Clarks has a troubleshooting page:

Troubleshooting - Engine

GL
J_AZ

mreid · 06-06-2013, 04:32 AM

Sounds like a timing issue to me.

John_AZ · 06-06-2013, 07:11 AM

Did you change the engine harness?

J_AZ

Chris71383 · 06-06-2013, 11:34 AM

john_AZ - I actually followed the engine removal and install guide on clarks and used thoose exact pages. That was one of my first thoughts was the plug wires were in the wrong order.

Is there any way to tell a speed and reference sensor apart easily? Unfortunatly I pulled the sensors out of the mounting block from both cars to wipe them off and since they had the same part number and connector I figured they were the same sensor, till I read thru that page to remount them. Fortunately one of the four sensors still had the tag on the cord, and there were two distinct types of printing for the part numbers between the four sensors. So by process of elimination I got them back in the right locations(I think) but I have no idea which is which of the remaining 2 sensors. As far as the .8mm washer to set the mounting bracket I made one on the lathe quick(sometimes having a small machine shop in your garage has its perks).

Thats the next step is to double check the timing marks.

Is it possible that the distributer is the issue, I did put a new distributer gasket on before I installed the distributer.

I used the harness from the 87' 944

mreid - thats my feeling, would having it off 1 tooth cause this?

John_AZ · 06-06-2013, 12:03 PM

You have to follow the pictures in the link for the reference sensors from Clarks to get the wires connected correctly and placed in the bell housing in the right spot. Set the .8mm gap carefully.

I looked at my hard copies of the WSM Electrical Vol 4 for the '87 944 and Vol 5 for the '88 924S. Without spending a lot of time comparing the two, I think you have to change the harness and put in the harness from the '88.

If you have a set or a download take a look.

Someone with more harness experience needs to reply.

I doubt changing the distributer gasket has any impact.

J_AZ

Chris71383 · 06-06-2013, 12:37 PM

Now I have another issue, went to work on the car and the battery was dead(on its way out anaway). Went and got a new battery, connected the neg. first, as soon as I touched the poitive the car starts cranking over like I'm trying to start it with the key.

jem60 · jem60's Garage

Use the 87 944 wiring harness as it fits the body. The 88 924s harness is similar to the early 944's with the dme under the dash. It doesn't fit the body. The late (87 ) harness integrates with the body properly. If you use the 88 924s harness, it does not hook up to the body properly without doing some rewiring.

Either dme will run the engine. Its preferable to use the 88 dme as it has some different mapping for fuel/timing due to the 10.2 compression ratio of the 1988 motor.,

As far as the starter issue, you've either got a crossed wire at the starter jumping the battery terminal to the starter solenoid or a crossed wire some place else. I've seen this before and can make a strange noise when you try to start the car.

Reference and speed sensors are the same part, but need to be connected to the proper connector. It's possible to switch the connectors at the rear of the engine.

Hope that helps

Capt Squid · 06-06-2013, 08:29 PM

As stated, your 87 944 harness will work fine. To get the most power out of the 88 engine you need an 88 DME and airflow meter. However it will run with the early AF meter.

Make sure your hose connections from the AF meter to the throttle body are tight.

Try switching the reference sensor connectors. I had them reversed on an engine install and it actually started. It cranked and cranked and acted like it wanted to start, finally kicked over, ran poorly for a few seconds and died. Switched the connectors and it fired right up. The consensus is that if you have the wires switched it will not start. I thought the same until this happened.

Chris71383 · 10:45 PM

thanks, that helps alot. As far as the battery issue, I have it isolated to one of the small ring terminals of 2 wires. Its the bundle that gives power to the dash, I'm wondering if it in the ignition.I had put the battery charger on it at 12v/2a overnight to try and top off the battery, right before I took it off it pegged the meter on the charger.

Chris71383 · 06-07-2013, 01:06 PM

Tried swaping the reference and speed sensors around and no dice, the car didn't even attempt to start with the plugs switched. As far as a starter issue, it seems that the solenoid on the starter was bad. I had disconnected the starter was trying to track down which wire was drawing the current, I reconnected it to try the car after I swap the plugs and the main post on the starter broke off as I tried to tighten the retaining nuts. Swapped out the solenoid from the starter on the 944, now you have to turn the key again to get the car to turn over.