Any links between these codes

Tiny
MHORTON
  • MEMBER
  • 1994 CHEVROLET CAVALIER
  • 156,000 MILES
1994 Cavalier 2.2, 4 cylinder. The problem started out as just a rough idle but over the last 5mo has turned into way worse problems. On cold start car is going through phases of delayed starting, needing starter fluid to start, using the fuel pump test wire to start and sometimes it will start on its own. None of these methods consistently start the car. One might work one time and you may have to use a different way the next. Once started it will usually jump***** and die at least one time. Usually re-starting it, it will stay running. It has developed into a problem that when driving with no or low throttle it will do the jumping******** and die thing (rarely dies). When in park the idle sometimes drops so low it almost dies but then catches up again. It almost sounds like its dropping a cylinder. When driving on the interstate you can feel the idle drop down and feel like it will die. It has extreme deep hesitation on take off and when you re-accelerate but if you ease the gas pedal it seems like it's not as deep and doesn't last as long. We have a day here or there where the car has it's rough idle but doesn't do any of the other major symptoms I have described(but those days are few). The current OBD1 GM codes are 35(improper idle possible IAC problem)We have replaced the IAC with no changes. Next code 19 (crank sensor fault)We put a brand new cps sensor still no changes. Next code 32 (EGR system problems)Replaced with brand new EGR valve still no changes. This is our only vehicle and my wife has a good job that we dont want her to loose. We would be grateful any help.I have wondered if it was a fuel pump problem but am not sure how any of these codes would relate to a fuel pump. We cannot afford to just throw parts at the car so we are trying to do the smart thing and try to go with the codes but they are getting us nowhere.
Do you
have the same problem?
Yes
No
Saturday, September 3rd, 2011 AT 11:41 PM

3 Replies

Tiny
JDL
  • EXPERT
The codes don't tell you what to replace, only that the system thinks there is a problem on the circuit, somehwere. How long since over-all tune-up? Use a gage and check fuel pressure. If there is no schrader valve for fuel pressure gage, you will need to tie into the supply line. Make sure, no pressure on fuel system before taking any lines loose.

Erase the codes and see what returns. If you think it is the fuel pump, check fuel pressure first, then check for good voltage and ground at the pump connector. When you first turn the key on, can you hear the pump run for a couple of seconds?
Was this
answer
helpful?
Yes
No
Sunday, September 4th, 2011 AT 8:22 PM
Tiny
MHORTON
  • MEMBER
We replaced the fuel pump and the car ran just fine for 2 days. Today when I went to leave for work the car only cranks and will not start. There is now no spark. I have attempted to test the ICM but cannot find the correct procedure because my modular only has 2 wires instead of 6 wires. The plugs and wires are new they were the first thing we started with in trouble shooting. All fluids were changed only 2 wks ago. Oxygen, MAP, IAC, TPS all have been changed. We cannot find the right obd1 scanner for home use and cannot afford to haul the car to a garage. The method of reading the codes from the engine light flashes does not seem to work on the car either. After replacing the fuel pump the crank time still seemed extended. The last 2 codes that came up before the no start were GM Codes 19 CPS sensor, and 35 IAC. Besides extended crank time on the start ups the car showed no signs of failure once the fuel pump was changed. The IAC is extending and retracting and seems to be working. The CPS I dont know exactly how many ohms it should read but when I ohm'd it, it was 2.02 (off car). We tested a new one and it read 2.01. So we did not purchase the new one.
Any help or direction would be greatly appreciated as the car isn't much but we need it. Thank you
Was this
answer
helpful?
Yes
No
Thursday, September 8th, 2011 AT 3:06 PM
Tiny
JDL
  • EXPERT
Should be 4 wires at ignition module, not counting spark plug wires. Could be 2 wires on each end, I'd have to look.

The crank sensor could cause a no spark issue. The crank sensor sends an rpm signal to pcm. Without that signal, no spark and no fuel injector pulse.

Below is wiring for ignition module.
Was this
answer
helpful?
Yes
No
Thursday, September 8th, 2011 AT 8:12 PM

Please login or register to post a reply.

Recommended Guides